Troy Ounce to Microgram Converter
Convert troy ounces to micrograms with our free online weight converter.
Quick Answer
1 Troy Ounce = 31103476.8 micrograms
Formula: Troy Ounce × conversion factor = Microgram
Use the calculator below for instant, accurate conversions.
Our Accuracy Guarantee
All conversion formulas on UnitsConverter.io have been verified against NIST (National Institute of Standards and Technology) guidelines and international SI standards. Our calculations are accurate to 10 decimal places for standard conversions and use arbitrary precision arithmetic for astronomical units.
Troy Ounce to Microgram Calculator
How to Use the Troy Ounce to Microgram Calculator:
- Enter the value you want to convert in the 'From' field (Troy Ounce).
- The converted value in Microgram will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Weight category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Troy Ounce to Microgram: Step-by-Step Guide
Converting Troy Ounce to Microgram involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Troy Ounce = 31103500 microgramsExample Calculation:
Convert 5 troy ounces: 5 × 31103500 = 155518000 micrograms
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
Need to convert to other weight units?
View all Weight conversions →What is a Troy Ounce and a Microgram?
1 troy ounce = 31.1034768 grams (g) = 480 grains
The troy ounce (abbreviated "oz t", "ozt", or "t oz") is a unit of mass in the troy weight system, used exclusively for precious metals and gemstones. It differs significantly from the avoirdupois ounce used in everyday measurements.
Troy vs. Avoirdupois: Critical Distinction
| Unit | Grams | Use Cases | |----------|-----------|---------------| | Troy ounce | 31.1034768 g | Precious metals (gold, silver, platinum), gemstones, pharmaceuticals (historic) | | Avoirdupois ounce | 28.349523125 g | Food, body weight, general commerce | | Difference | +2.754 g (9.7% heavier) | Troy ounce is HEAVIER |
Critical for buyers: If someone sells you "1 ounce of gold" using avoirdupois ounces instead of troy ounces, you're getting 9.7% less metal than you paid for!
The Troy Weight System
Unlike the avoirdupois system (16 ounces = 1 pound), the troy system uses different ratios:
- 24 grains = 1 pennyweight (dwt)
- 20 pennyweights = 1 troy ounce (oz t)
- 12 troy ounces = 1 troy pound (lb t)
Paradox: The troy ounce is heavier than the avoirdupois ounce, BUT the troy pound (373.24 g) is lighter than the avoirdupois pound (453.59 g) because it contains only 12 ounces instead of 16!
Why Troy Ounces Persist
Despite global metrication, troy ounces remain dominant in precious metals for these reasons:
- Market convention: Centuries of gold/silver trading established price benchmarks in troy ounces
- Legal tender: U.S. Mint, Royal Canadian Mint, and others mint official coins in troy ounce denominations
- Futures contracts: COMEX gold contracts specify 100 troy ounces per contract
- LBMA standards: London Bullion Market Association requires troy ounce quotations
- Central banks: Gold reserves reported in troy ounces (e.g., Fort Knox holds 147.3 million oz t)
A microgram (symbol: µg or mcg) is a unit of mass in the metric system equal to one millionth (1/1,000,000) of a gram, or one thousandth (1/1,000) of a milligram.
Key relationships:
- 1 microgram = 0.000001 grams (g)
- 1 microgram = 0.001 milligrams (mg)
- 1,000 micrograms = 1 milligram
- 1,000,000 micrograms = 1 gram
- 1 microgram ≈ 0.0000000353 ounces
Symbol variations:
- µg: Standard scientific symbol (µ = Greek letter mu)
- mcg: Common in medicine/pharmacy (avoids confusion if µ looks like m)
- Both mean exactly the same thing
The prefix "micro-":
- From Greek "mikrós" meaning "small"
- SI prefix denoting 10⁻⁶ (one millionth)
- Also used in: micrometer (µm), microsecond (µs), microliter (µL)
In perspective (how small is it?):
- 1 grain of table salt ≈ 1,000 µg (1 mg)
- 1 speck of dust ≈ 1-10 µg
- Human red blood cell ≈ 100 µg
- A typical dose of Vitamin B12 ≈ 2.4 µg
⚠️ CRITICAL SAFETY WARNING: Never confuse µg (microgram) with mg (milligram). Taking 1 mg when prescribed 1 µg = 1,000x overdose! Always double-check labels and prescriptions.
Note: The Troy Ounce is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Microgram belongs to the metric (SI) system.
History of the Troy Ounce and Microgram
Ancient and Medieval Origins (Pre-1500)
The word "ounce" derives from the Latin "uncia" (one-twelfth), reflecting the Roman system where 1 uncia = 1/12 of a libra (pound). The troy system's specific origins trace to Troyes, France, a major European trade city.
12th-15th centuries - Champagne Fairs: Troyes hosted international trade fairs where merchants from Italy, Flanders, England, and German states exchanged goods. Precious metals, spices, and textiles required standardized weights. The "Troyes weight" system emerged as a trusted standard for valuable commodities, particularly gold, silver, and gemstones.
Why "troy" not "avoirdupois"? Two parallel weight systems developed:
- Troy weights: For precious metals, spices, medicines (high-value, small quantities)
- Avoirdupois weights: For bulk goods like wool, grain, iron (from French "avoir de pois" = goods of weight)
English Standardization (1500-1800)
1527 - King Henry VIII standardization: Henry VIII officially defined troy weights for the English realm, establishing:
- 1 troy pound = 5,760 grains
- 1 troy ounce = 480 grains
- 1 grain = 64.79891 milligrams (based on barley grain weight)
1758 - British assay offices: The Goldsmiths' Company and assay offices in London, Birmingham, Sheffield, and Edinburgh used troy ounces exclusively for hallmarking gold and silver items. This reinforced troy ounces as the legal standard for precious metals in British commerce.
The Tower Pound obsolescence: England previously used the "Tower pound" for minting coins (5,400 grains), but troy weights (5,760 grains per pound) eventually replaced it in 1527, creating unified standards for bullion and coinage.
American Adoption (1776-1900)
1776-1792 - Early United States: American colonies inherited British troy standards. The early U.S. used Spanish silver dollars and British gold sovereigns, all measured in troy ounces.
1828 - U.S. Coinage Act: Congress officially adopted troy weights for all U.S. coinage. The Act specified:
- Gold dollar = 25.8 grains (1.672 g) of 90% gold
- Silver dollar = 412.5 grains (26.73 g) of 90% silver
- All coins measured in troy grains
1849-1855 - California Gold Rush: The discovery of gold at Sutter's Mill created massive demand for standardized weights. Assay offices in San Francisco weighed gold dust and nuggets in troy ounces, establishing the unit in the American West.
1873 - Coinage Act ("Crime of 1873"): This act demonetized silver, ending bimetallism. However, troy ounces remained the standard for measuring both gold and silver bullion.
Global Standardization (1900-Present)
1900-1971 - The Gold Standard era: Most nations tied currencies to gold reserves, measured in troy ounces:
- 1900: Gold Standard Act (U.S. fixed $20.67 per troy ounce)
- 1933: FDR revalued gold to $35 per troy ounce
- 1944: Bretton Woods Agreement ($35/oz t peg)
- 1971: Nixon ended gold convertibility, but troy ounce pricing persisted
1919 - London Bullion Market Association (LBMA): Founded to standardize London gold market practices. LBMA established:
- Good Delivery bars: 350-430 troy ounces (typically 400 oz t)
- Minimum purity: 995 parts per 1,000 (99.5% pure gold)
- Troy ounce quotations for spot prices
1974 - COMEX gold futures: The Commodity Exchange (COMEX) in New York launched gold futures contracts:
- Contract size: 100 troy ounces
- Delivery specifications: 1 kg bars (32.1507 oz t) or 100 oz bars
- Global price discovery mechanism
1975 - Gold ownership legalization: U.S. citizens regained the right to own gold bullion (banned since 1933). Investment coins like the Krugerrand (1 oz t), Canadian Maple Leaf (1 oz t), and American Gold Eagle (1 oz t) popularized troy ounce denominations for retail investors.
2000s-Present - Digital age: Despite metrication, troy ounces dominate:
- ETFs: SPDR Gold Shares (GLD) holds 900+ tons (28.9M oz t)
- Central banks: Reserve holdings reported in troy ounces (U.S. 261.5M oz t, Germany 108.9M oz t)
- Spot prices: Bloomberg, Reuters, Kitco quote gold/silver per troy ounce
- Refineries: Swiss refiners (PAMP, Valcambi) produce bars in troy ounce sizes
Cultural Significance
The troy ounce represents continuity in global finance—a medieval trade standard that survived the industrial revolution, world wars, and digital transformation. While most historical units vanished with metrication, the troy ounce persists because precious metals markets value tradition, legal precedent, and universal standardization over decimal convenience.
-
Metric System Origins: The microgram is derived from the gram, a base unit in the early metric system defined in the late 18th century during the French Revolution (1790s).
-
Prefix Development: The prefix "micro-" (symbol: µ) was formalized in the late 19th century as part of the systematic development of metric prefixes to indicate a factor of 10⁻⁶ (one millionth).
-
Scientific Need: As analytical chemistry and biology advanced in the 19th and early 20th centuries, scientists needed to measure increasingly smaller masses - leading to widespread adoption of the microgram.
-
Pharmaceutical Revolution: The microgram became critically important in the 20th century with:
- Development of potent hormones (thyroid, insulin)
- Discovery of vitamins requiring trace amounts
- Creation of modern pharmaceuticals with precise dosing
- Antibiotics and specialized medications
-
Vitamin Discovery Era (1910s-1940s):
- Scientists discovered vitamins needed in microgram quantities
- Vitamin B12, biotin, folate measured in µg
- Nutrition labels began using micrograms
- Public health campaigns addressed micronutrient deficiencies
-
Symbol Standardization:
- µg adopted as standard scientific notation
- mcg introduced in medical settings to prevent confusion (µ can look like m if handwritten poorly)
- Both symbols officially recognized and equivalent
-
Modern Usage: Today, micrograms are essential in:
- Pharmaceutical dosing (especially endocrinology)
- Nutritional labeling (vitamins, minerals)
- Environmental monitoring (air/water quality)
- Toxicology and forensic science
- Analytical chemistry (trace analysis)
Common Uses and Applications: troy ounces vs micrograms
Explore the typical applications for both Troy Ounce (imperial/US) and Microgram (metric) to understand their common contexts.
Common Uses for troy ounces
1. Precious Metals Trading
The troy ounce is the universal standard for global bullion markets:
Spot price quotations:
- Gold: $1,800-2,100 per troy ounce (fluctuates with markets)
- Silver: $20-30 per oz t
- Platinum: $900-1,200 per oz t
- Palladium: $1,000-1,600 per oz t
- Rhodium: $3,000-15,000 per oz t (highest volatility)
Major markets:
- London Bullion Market (LBMA): Sets gold/silver fix twice daily in troy ounces
- COMEX (New York): Futures contracts (100 oz t gold, 5,000 oz t silver)
- Shanghai Gold Exchange: Trades gold in grams but converts to oz t for international quotes
- Dubai Gold Souk: Retail sales in grams, wholesale in troy ounces
Why troy ounces persist: Centuries of price history, legal contracts, and central bank reserves create network effects—changing to grams would require recalibrating trillions in financial instruments.
2. Investment Coins & Bars
Government minted coins (1 oz troy):
- American Gold Eagle: Most popular U.S. bullion coin, 22K gold
- Canadian Maple Leaf: 24K gold (.9999 fine), iconic design
- South African Krugerrand: First modern bullion coin (1967)
- Austrian Philharmonic: European alternative, euro-denominated
- Chinese Gold Panda: Annual design changes, collector value
Fractional coins:
- 1/2 oz, 1/4 oz, 1/10 oz troy ounce denominations
- Higher premiums per ounce (manufacturing costs)
- Easier to liquidate small amounts
Private mint bars:
- 1 oz, 10 oz, 100 oz troy ounce sizes (silver)
- 1 oz, 10 oz, 1 kg gold bars
- Lower premiums than coins (no numismatic value)
- Stackability for storage
3. Jewelry Manufacturing
Jewelers purchase gold in troy ounces but often work in grams or pennyweights (dwt):
Pricing structure:
- Spot price: Current troy ounce price (e.g., $2,000/oz)
- Karat adjustment: 14K = 58.3%, 18K = 75%, 22K = 91.67%
- Fabrication cost: Labor, design, gemstones
- Retail markup: 2-3× material cost
Example calculation (14K ring):
- Weight: 5 grams = 0.16075 oz t
- Pure gold: 0.16075 × 0.583 = 0.0938 oz t
- Gold value: 0.0938 × $2,000 = $187.60
- Retail price: $500-800 (includes labor, overhead, profit)
Scrap gold recycling: Jewelers sell scrap in troy ounces to refineries, receiving 90-95% of spot price (refining losses, processing fees).
4. Pharmaceutical & Apothecary (Historic)
Before metrication, pharmacists used troy weights for compounding:
Apothecaries' system:
- 20 grains = 1 scruple
- 3 scruples = 1 dram
- 8 drams = 1 troy ounce
Modern legacy:
- Grain measurements persist (aspirin: 5 grains = 325 mg)
- Troy ounces phased out in medicine by 1970s
- Replaced by milligrams and grams for precision
5. Mining & Geology
Gold production and ore grades measured in troy ounces:
Reserve reporting:
- Gold deposits: "10 million oz t at 2 g/t grade" (metric tons ore, troy ounces gold)
- Production rates: "500,000 oz t per year" (annual mine output)
Ore grades:
- High-grade: 10-20 g/t (0.32-0.64 oz t per metric ton ore)
- Low-grade: 1-5 g/t (0.032-0.16 oz t/t)
- Ultra-low-grade: 0.5 g/t (economical with modern extraction)
Example (Nevada Gold Mine):
- Reserves: 50 million metric tons
- Grade: 2 g/t (0.064 oz t/t)
- Contained gold: 3.2 million troy ounces
- Mine life: 15 years (213,000 oz t/year production)
6. Central Banking & Reserves
Countries hold gold reserves measured in troy ounces:
Reserve valuation: Most central banks value gold at historic cost ($42.22/oz t, a 1973 price), not market rates. However, market value uses current spot prices:
- U.S. reserves: 261.5M oz t × $2,000 = $523 billion market value
- Official books: 261.5M oz t × $42.22 = $11 billion (!)
Reserve diversification:
- Gold as % of reserves: U.S. (70%), Germany (67%), Italy (64%)
- Rationale: Inflation hedge, currency crisis protection, geopolitical insurance
7. Collectibles & Numismatics
Coin collectors distinguish between bullion value (troy ounces) and numismatic value (rarity, condition):
Example: 1933 Double Eagle
- Gold content: 0.9675 oz t (~$1,935 melt value)
- Auction price: $18.9 million (2021 Sotheby's)
- Numismatic premium: 9,700× bullion value!
Modern bullion vs. collectible:
- Bullion: Trades at spot + 3-10% premium (1 oz Gold Eagle)
- Collectible: Rare dates, low mintages command 2-100× premiums
When to Use micrograms
The microgram is essential for measuring extremely small quantities across multiple fields:
Medicine & Pharmaceuticals
Measuring dosages of potent medications and hormones where milligrams would be too large a unit. Critical for endocrinology, psychiatry, and specialized therapeutics.
Why micrograms matter:
- Potent drugs have narrow therapeutic windows
- Prevents overdose from rounding errors
- Allows fine-tuning of hormone replacement
- Essential for pediatric dosing
Common medications in µg:
- Thyroid hormones (25-200 µg)
- Birth control (15-35 µg estrogen)
- Vitamin B12 supplements (100-1,000 µg)
- Folic acid (400-800 µg)
- Digoxin (62.5-250 µg)
⚠️ Safety: Pharmacists use mcg (not µg) on prescriptions to prevent µ being misread as m.
Convert medication doses: µg to mg | mg to µg
Nutrition
Specifying amounts of trace minerals and vitamins in food, especially those needed in very small quantities but essential for health.
Nutrients measured in µg:
- Vitamin B12 (2.4 µg/day)
- Vitamin D (10-20 µg/day)
- Vitamin K (90-120 µg/day)
- Folate (400 µg/day)
- Selenium (55 µg/day)
- Biotin (30 µg/day)
Why µg for nutrition:
- Daily requirements are very small
- Prevents decimal errors (easier than 0.0024 g)
- International standard for supplement labeling
- Matches medical terminology
Food Fortification:
- Breakfast cereals: Fortified with µg amounts of B vitamins
- Milk: Vitamin D added in µg
- Salt: Iodine fortification (45-100 µg per gram of salt)
Chemistry & Biology
Quantifying trace amounts of substances in experiments, especially in analytical chemistry, biochemistry, and molecular biology.
Laboratory Applications:
- Sample preparation: Weighing µg of rare compounds
- Protein quantification: Bradford/BCA assays use µg protein
- DNA/RNA: Quantified in µg for PCR, sequencing
- HPLC/GC: Injection standards in µg amounts
- Mass spectrometry: Detection at µg to pg levels
Biochemical Standards:
- Enzyme activity: Units per µg protein
- Cell culture: Growth factors at 1-100 µg/mL
- Antibody concentration: Often µg/mL
Environmental Science
Measuring concentrations of pollutants or contaminants in air, water, and soil at parts-per-million (ppm) or parts-per-billion (ppb) levels.
Environmental Monitoring:
-
Air quality: µg/m³ (micrograms per cubic meter)
- PM2.5 particulates
- Heavy metals (lead, mercury)
- Volatile organic compounds (VOCs)
-
Water quality: µg/L (micrograms per liter = ppb)
- Arsenic, lead, mercury in drinking water
- Pesticide residues
- Pharmaceutical contaminants
- Microplastics
-
Soil contamination: µg/kg (micrograms per kilogram = ppb)
- Heavy metal contamination
- Persistent organic pollutants
Regulatory Standards:
- EPA sets limits in µg/m³ or µg/L
- WHO guidelines use µg measurements
- EU environmental regulations
Toxicology and Forensics
Measuring extremely small amounts of toxic substances, drugs, or poisons in biological samples.
Forensic Toxicology:
- Blood drug levels (µg/L)
- Urine drug screening (µg/mL)
- Hair analysis (µg/mg hair)
- Tissue samples (µg/g tissue)
Clinical Toxicology:
- Heavy metal poisoning (blood lead: µg/dL)
- Drug overdose assessment
- Therapeutic drug monitoring
- Poison detection
Detection Limits:
- Modern instruments: Can detect picograms (0.001 µg)
- High sensitivity needed for trace toxins
Research and Development
Pharmaceutical R&D, materials science, and nanotechnology use micrograms for:
- Drug formulation studies
- Nanoparticle synthesis
- Catalyst development
- Biosensor fabrication
- Quality control testing
Use our weight converter for scientific conversions.
Additional Unit Information
About Troy Ounce (oz t)
1. Is a troy ounce the same as a regular ounce?
No. The troy ounce (31.1035 g) is about 9.7% heavier than the avoirdupois ounce (28.3495 g) used for food and general items.
Visual comparison:
- 1 troy ounce gold = Size of a large grape (but very dense)
- 1 avoirdupois ounce flour = Same volume but less mass
When it matters: Precious metals (gold, silver, platinum) always use troy ounces. If someone offers you "1 ounce of gold" at a suspiciously low price, verify it's troy ounces—not avoirdupois!
2. How many grams are in a troy ounce?
Exactly 31.1034768 grams.
This precise definition comes from the 1959 international agreement on units. It's the same globally—LBMA (London), COMEX (New York), and Shanghai Gold Exchange all use this exact conversion.
For practical purposes:
- 1 troy oz ≈ 31.1 grams (rounded)
- 10 troy oz ≈ 311 grams
- 32.15 troy oz = 1 kilogram (exactly 1,000 g)
3. How many troy ounces are in a troy pound?
12 troy ounces = 1 troy pound (373.24 grams).
This differs from the avoirdupois system where 16 ounces = 1 pound. The troy system uses base-12 (duodecimal), a remnant of Roman and medieval counting systems.
Paradox explained:
- Troy ounce (31.10 g) > Avoirdupois ounce (28.35 g)
- BUT Troy pound (373.24 g) < Avoirdupois pound (453.59 g)
Why: 12 × 31.10 = 373.24, while 16 × 28.35 = 453.59.
4. Why do precious metals use troy ounces instead of grams?
Historical inertia and market convention.
Reasons troy ounces persist:
-
Centuries of price data: Gold has been priced per troy ounce since the 1700s. Changing would break historical charts and analysis.
-
Legal tender and contracts: U.S. Mint, Canadian Mint, and others legally define coins in troy ounces. Futures contracts, options, and derivatives are denominated in oz t.
-
Central bank reserves: Fort Knox holds "147.3 million troy ounces," not "4,582.7 metric tons"—the legal records use troy ounces.
-
Network effects: If London uses oz t, New York must too. Shanghai converts grams to oz t for international quotes.
-
Cultural identity: "An ounce of gold" evokes tangibility. "31.1 grams of gold" lacks the same resonance.
Metrication attempts failed: France and other metric-first countries tried quoting gold in grams, but international traders kept converting back to oz t for comparison.
5. How much is 1 troy ounce of gold worth?
It fluctuates constantly. As of 2024, gold trades between $1,800 - $2,100 per troy ounce, depending on economic conditions.
Price drivers:
- Inflation fears: Gold rises when currency value erodes
- Interest rates: Low rates → gold attractive (no yield anyway)
- Geopolitical crises: Wars, sanctions boost safe-haven demand
- Central bank buying: China, Russia, Turkey accumulating reserves
- Jewelry demand: India, China seasonal festivals
Historical context:
- 1900: $20.67/oz (Gold Standard Act)
- 1971: $35/oz (Nixon Shock, end of Bretton Woods)
- 1980: $850/oz (Hunt Brothers silver crisis, inflation)
- 2011: $1,900/oz (Financial crisis aftermath)
- 2020: $2,067/oz (COVID-19 pandemic peak)
Real-time prices: Check Bloomberg, Reuters, Kitco, or bullion dealer sites.
6. What's the difference between "carat" and "karat"?
Completely different units—one measures weight, the other purity:
CARAT (ct) = Gemstone weight
- 1 carat = 200 milligrams = 0.00643 troy ounces
- Measures diamonds, rubies, sapphires, emeralds
- "5-carat diamond" = 1 gram weight
KARAT (K or kt) = Gold purity
- 24K = 100% pure gold
- 18K = 75% gold (18/24)
- 14K = 58.3% gold (14/24)
- Measures alloy composition, not weight
Example: "18K gold ring weighing 0.2 troy ounces" means:
- Karat: 75% pure (18/24)
- Weight: 0.2 oz t = 6.22 g total
- Pure gold: 0.15 oz t = 4.67 g (6.22 × 0.75)
7. Can I buy fractional troy ounces?
Yes! Governments and private mints produce fractional coins:
Common sizes:
- 1/10 oz t (3.11 g) — Popular for small investors
- 1/4 oz t (7.78 g)
- 1/2 oz t (15.55 g)
- 1 oz t (31.10 g) — Most popular size
Trade-offs:
- Pros: Lower entry cost ($200 for 1/10 oz vs. $2,000 for 1 oz), easier to liquidate small amounts
- Cons: Higher premiums per ounce (1/10 oz costs ~15% premium vs. 3-5% for 1 oz)
Example:
- 1 oz Gold Eagle: $2,050 ($50 premium over $2,000 spot = 2.5%)
- 1/10 oz Gold Eagle: $240 ($40 premium over $200 spot = 20%!)
Why higher premiums? Minting costs don't scale linearly. Striking a 1/10 oz coin costs almost as much as a 1 oz coin, so the percentage premium is higher.
8. What is a "Good Delivery" gold bar?
The international standard for large-scale gold bullion, set by the London Bullion Market Association (LBMA).
Specifications:
- Weight: 350-430 troy ounces (typically 400 oz t = 12.4 kg)
- Purity: Minimum 995 parts per 1,000 (99.5% pure gold)
- Fineness stamp: Refinery mark, serial number, purity, year
- Refiners: LBMA-approved list (~70 refineries: PAMP, Valcambi, Rand, Johnson Matthey)
Why "Good Delivery"? Before standardization, banks had to assay every bar (costly, time-consuming). LBMA Good Delivery certification means bars are universally accepted without re-assaying.
Where they're used:
- Central bank reserves (Fort Knox, Bank of England vaults)
- Commercial bank vaults (HSBC, JPMorgan)
- ETF backing (SPDR Gold Shares stores Good Delivery bars)
Retail availability: Most investors never see Good Delivery bars—they're institutional. Retail investors buy 1 oz coins or small bars (1 oz, 10 oz, 100 oz).
9. How do I convert troy ounces to kilograms?
Formula:
1 troy ounce = 0.0311034768 kilograms
OR
1 kilogram = 32.1507466 troy ounces
Quick method: Divide troy ounces by 32.15 to get kilograms:
400 oz t ÷ 32.15 ≈ 12.44 kg
Precise method: Multiply troy ounces by 0.0311034768:
400 oz t × 0.0311034768 = 12.44139072 kg (EXACT)
Common conversions:
- 1 oz t = 0.0311 kg
- 10 oz t = 0.311 kg
- 100 oz t = 3.11 kg
- 1,000 oz t = 31.1 kg
- 32.15 oz t = 1 kg (exactly 1,000 g)
10. What's the smallest amount of gold I can buy?
Technically, you can buy any amount, but practical minimums exist:
Physical gold:
- Smallest coins: 1/10 oz t (~$200-250)
- Gold jewelry: Varies, but 14K chains start around $100-200 (contains ~0.05 oz t pure gold)
- Gold leaf: Decorative, negligible weight (~0.001 oz t per sheet)
Paper gold (no physical delivery):
- Gold ETFs (GLD, IAU): 1 share ≈ 0.1 oz t (~$200)
- Fractional platforms (OneGold, Vaulted): Buy as little as $1 worth (0.0005 oz t)
- Futures contracts: 100 oz t minimum (~$200,000—professional traders only)
Recommendation for beginners: Start with 1/4 oz or 1/2 oz coins (balance between affordability and premiums). Avoid tiny fractions (1/20 oz) due to extremely high premiums.
11. How do jewelers measure gold?
Three units, depending on context:
- Troy ounces (oz t): Buying gold from refineries, calculating melt value
- Pennyweights (dwt): Traditional unit (1 oz t = 20 dwt, 1 dwt = 1.555 g)
- Grams (g): Modern standard, easier math
Example (jeweler selling 14K scrap):
- Weighs scrap: 25.5 grams
- Converts to troy ounces: 25.5 ÷ 31.1 = 0.82 oz t
- Calculates pure gold: 0.82 × 0.583 (14K) = 0.478 oz t
- Refinery pays: 0.478 × $2,000 × 0.95 = $908 (95% of spot, 5% refining fee)
Pennyweight legacy: Older jewelers still use "dwt" for historic reasons. Most modern shops use grams for precision.
12. Why are central banks buying more gold?
Diversification away from the U.S. dollar and geopolitical hedging.
Key drivers:
- De-dollarization: Russia, China, Turkey reducing USD reserves after sanctions
- Inflation hedge: 2020-2024 inflation spikes drove safe-haven demand
- Currency debasement fears: Massive money printing (COVID stimulus) erodes fiat value
- Geopolitical tensions: Ukraine war, Taiwan tensions increase reserve gold holdings
Recent trends (2020-2024):
- China: Added 300+ tons (9.6M oz t) in 2023 alone
- Russia: Doubled reserves to 2,300 tons (74M oz t) before Ukraine war
- Poland: Increased from 103 to 228 tons (7.3M oz t)
- Singapore: Tripled reserves to 230 tons (7.4M oz t)
Why troy ounces matter: Central bank transactions are reported in troy ounces (IMF, World Gold Council standards), even though storage is often measured in metric tons.
About Microgram (µg)
How many micrograms are in a milligram?
There are 1,000 micrograms (µg) in 1 milligram (mg).
Conversion:
- 1 mg = 1,000 µg
- To convert mg to µg: multiply by 1,000
- To convert µg to mg: divide by 1,000
Examples:
- 0.5 mg = 500 µg
- 1.5 mg = 1,500 µg
- 0.025 mg = 25 µg
- 10 mg = 10,000 µg
Memory aid: "Milli" is bigger than "micro" - mg is 1,000 times larger than µg.
Use our mg to µg converter for instant conversions.
How many micrograms are in a gram?
There are 1,000,000 micrograms (µg) in 1 gram (g).
Calculation: 1 g = 1,000 mg, and 1 mg = 1,000 µg, therefore: 1 g = 1,000 × 1,000 µg = 1,000,000 µg
Conversion:
- 1 g = 1,000,000 µg
- To convert g to µg: multiply by 1,000,000
- To convert µg to g: divide by 1,000,000
Examples:
- 0.001 g = 1,000 µg
- 0.01 g = 10,000 µg
- 0.1 g = 100,000 µg
- 1 g = 1,000,000 µg
Perspective: A grain of salt (~1 mg) contains ~1,000 µg.
What is the symbol for microgram?
The standard symbol is µg (using the Greek letter µ, pronounced "mu").
Alternative symbol: mcg (used especially in medical contexts)
Why two symbols?:
- µg: Standard scientific notation, internationally recognized
- mcg: Safer in medical prescriptions - prevents µ being misread as m
- Both mean exactly the same thing: 1 µg = 1 mcg
Safety issue:
- Handwritten µ can look like m
- "µg" misread as "mg" = 1,000x dosing error
- Medical professionals prefer "mcg" to prevent fatal errors
How to type µ:
- Mac: Option + M
- Windows: Alt + 230
- Or just type "mcg" in medical contexts
Is µg the same as mcg?
Yes! µg and mcg mean exactly the same thing.
- µg: Microgram (using Greek letter µ)
- mcg: Microgram (using letters m-c-g)
- Both = 0.001 mg = 0.000001 g
Why both exist?:
- µg: Standard in science, chemistry, environmental science
- mcg: Preferred in medicine/pharmacy for safety
- Prevents µ being misread as m (which would be mg)
Where you'll see each:
- µg: Scientific papers, environmental reports, lab results
- mcg: Prescription bottles, medical records, pharmacy labels
- Both: Nutrition labels (may show either or both)
Important: Always verify which unit - never assume!
How much is 1 microgram visually?
1 microgram is EXTREMELY small - too small to see with the naked eye.
Visual comparisons:
- 1,000 µg = 1 mg = 1 grain of table salt
- 100 µg = Approximate weight of a human red blood cell
- 10 µg = Large grain of pollen
- 1 µg = Small speck of dust
Perspective:
- 1 paperclip ≈ 1,000,000 µg (1 gram)
- 1 grain of salt ≈ 1,000 µg (1 mg)
- 1 eyelash ≈ 10-100 µg
- 1 human hair (1 cm) ≈ 60-90 µg
For medication:
- A typical Vitamin B12 tablet (1,000 µg) looks like any small pill
- The active ingredient weighs 1 mg
- The rest is filler/binder
You cannot "see" individual micrograms - you need a precision scale to measure them accurately.
What medications are dosed in micrograms?
Many potent medications use microgram dosing:
Thyroid Hormones (most common):
- Levothyroxine: 25-200 µg
- Liothyronine: 5-50 µg
Hormonal Medications:
- Birth control pills: 15-35 µg estrogen
- Testosterone: Some formulations
Cardiovascular:
- Digoxin: 62.5-250 µg
- Clonidine: 100-600 µg
Pain Management:
- Fentanyl: Patches deliver µg/hour
- (Fentanyl is EXTREMELY potent - µg doses)
Vitamins (technically supplements):
- Vitamin B12: 100-5,000 µg
- Vitamin D: 10-125 µg (400-5,000 IU)
- Folate: 400-800 µg
- Biotin: 30-10,000 µg
Why micrograms?:
- Very potent drugs need small doses
- Narrow therapeutic window
- Prevents overdose from measurement errors
⚠️ Safety: These medications have microgram-level dosing precisely because they're potent. Never adjust dose without medical supervision.
How do I measure micrograms at home?
Short answer: You generally CAN'T and SHOULDN'T measure micrograms at home.
Why not?:
- Kitchen scales: Accurate to 1 gram (1,000,000 µg) - NOT precise enough
- Jewelry scales: Accurate to 0.01-0.1 g (10,000-100,000 µg) - still not precise
- Milligram scales: Accurate to 1 mg (1,000 µg) - closer but not µg-level
- Microgram precision: Requires laboratory analytical balance ($1,000-$10,000)
For Medications:
- ✅ Use pre-measured tablets/capsules - safest option
- ✅ Follow prescription exactly - don't compound at home
- ✅ Liquid medications: Use provided dropper/syringe
- ❌ Never try to measure powder medications at home
For Supplements:
- Buy pre-dosed pills (e.g., 1,000 µg B12 tablets)
- Use products with certified dosing
- Don't buy raw powder unless you're a lab
If you need microgram precision:
- Laboratory analytical balance required
- Calibrated weights for accuracy
- Controlled environment (no air currents)
- Cost: $1,000+ for quality balance
Safety warning: ⚠️ For medications, NEVER attempt home measurement. Fatal dosing errors possible. Always use professionally prepared medications.
What's the difference between µg/mL and mg/L?
They are exactly the same!
µg/mL = mg/L (both equal parts per million in water)
Why?:
- 1 mL = 0.001 L (or 1 L = 1,000 mL)
- 1 mg = 1,000 µg
- Therefore: 1 mg/L = 1,000 µg/1,000 mL = 1 µg/mL
Examples:
- Lead in water: 15 µg/L = 0.015 mg/L
- Drug concentration: 100 µg/mL = 100 mg/L
- Vitamin solution: 50 µg/mL = 50 mg/L
Common uses:
- µg/mL: Laboratory concentrations, drug solutions
- mg/L: Environmental standards, water quality
- Both: Used interchangeably depending on field
Parts per million (ppm):
- In water: 1 ppm = 1 mg/L = 1 µg/mL
- In air: 1 ppm is different (depends on molecular weight)
How many IU is a microgram?
It depends on which vitamin! IU (International Units) convert differently for each substance.
Vitamin D (most common):
- 1 µg = 40 IU
- 1 IU = 0.025 µg
Common Vitamin D conversions:
- 400 IU = 10 µg
- 800 IU = 20 µg
- 1,000 IU = 25 µg
- 2,000 IU = 50 µg
- 5,000 IU = 125 µg
Vitamin A (retinol):
- 1 IU ≈ 0.3 µg retinol
- 1 µg retinol ≈ 3.33 IU
Vitamin E (α-tocopherol):
- 1 IU ≈ 0.67 mg α-tocopherol
- (Note: mg not µg for Vitamin E!)
Why different?:
- IU measures biological activity, not mass
- Each vitamin has different potency
- Historical measurement system
- Modern labels often show both µg and IU
Tip: Check supplement labels - most show both µg and IU for clarity.
What is µg/dL in blood tests?
µg/dL = micrograms per deciliter - commonly used in blood test results.
What it means:
- Concentration of a substance in blood
- 1 dL = 100 mL (1 deciliter = 10th of a liter)
- µg/dL tells you: micrograms per 100 milliliters of blood
Common blood tests using µg/dL:
Blood Lead Level:
- Normal: <5 µg/dL
- Elevated: 5-10 µg/dL
- High: >10 µg/dL (concern)
- Toxic: >45 µg/dL
Blood Glucose (note: mg/dL, not µg/dL):
- Normal fasting: 70-100 mg/dL
- (This is milligrams, not micrograms!)
Iron/Ferritin: Sometimes reported in µg/dL Vitamin B12: Often ng/mL or pg/mL (nanograms/picograms)
Conversion:
- 1 µg/dL = 10 µg/L
- 1 µg/dL = 0.01 mg/L
- 1 µg/dL = 10 ng/mL
Clinical significance:
- Reference ranges vary by lab
- Always check lab's normal range
- Consult healthcare provider for interpretation
Note: µg/dL is different from µg/mL:
- 1 µg/dL = 0.01 µg/mL (100 times smaller)
Conversion Table: Troy Ounce to Microgram
| Troy Ounce (oz t) | Microgram (µg) |
|---|---|
| 0.5 | 15,551,738.4 |
| 1 | 31,103,476.8 |
| 1.5 | 46,655,215.2 |
| 2 | 62,206,953.6 |
| 5 | 155,517,384 |
| 10 | 311,034,768 |
| 25 | 777,586,920 |
| 50 | 1,555,173,840 |
| 100 | 3,110,347,680 |
| 250 | 7,775,869,200 |
| 500 | 15,551,738,400 |
| 1,000 | 31,103,476,800 |
People Also Ask
How do I convert Troy Ounce to Microgram?
To convert Troy Ounce to Microgram, enter the value in Troy Ounce in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our weight converter page to convert between other units in this category.
Learn more →What is the conversion factor from Troy Ounce to Microgram?
The conversion factor depends on the specific relationship between Troy Ounce and Microgram. You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.
Can I convert Microgram back to Troy Ounce?
Yes! You can easily convert Microgram back to Troy Ounce by using the swap button (⇌) in the calculator above, or by visiting our Microgram to Troy Ounce converter page. You can also explore other weight conversions on our category page.
Learn more →What are common uses for Troy Ounce and Microgram?
Troy Ounce and Microgram are both standard units used in weight measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our weight converter for more conversion options.
For more weight conversion questions, visit our FAQ page or explore our conversion guides.
Helpful Conversion Guides
Learn more about unit conversion with our comprehensive guides:
📚 How to Convert Units
Step-by-step guide to unit conversion with practical examples.
🔢 Conversion Formulas
Essential formulas for weight and other conversions.
⚖️ Metric vs Imperial
Understand the differences between measurement systems.
⚠️ Common Mistakes
Learn about frequent errors and how to avoid them.
All Weight Conversions
Other Weight Units and Conversions
Explore other weight units and their conversion options:
- Kilogram (kg) • Troy Ounce to Kilogram
- Gram (g) • Troy Ounce to Gram
- Milligram (mg) • Troy Ounce to Milligram
- Pound (lb) • Troy Ounce to Pound
- Ounce (oz) • Troy Ounce to Ounce
- Stone (st) • Troy Ounce to Stone
- Ton (metric) (t) • Troy Ounce to Ton (metric)
- Ton (US) (ton) • Troy Ounce to Ton (US)
- Ton (UK) (long ton) • Troy Ounce to Ton (UK)
- Carat (ct) • Troy Ounce to Carat
Verified Against Authority Standards
All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.
National Institute of Standards and Technology — US standards for weight and mass measurements
International Organization for Standardization — International standard for mechanics quantities
Last verified: December 3, 2025