Troy Ounce to Gram Converter

Convert troy ounces to grams with our free online weight converter.

Quick Answer

1 Troy Ounce = 31.103477 grams

Formula: Troy Ounce × conversion factor = Gram

Use the calculator below for instant, accurate conversions.

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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.

Last verified: December 2025|Reviewed by: Sam Mathew, Software Engineer

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How to Use the Troy Ounce to Gram Calculator:

Enter the value you want to convert in the 'From' field (Troy Ounce).
The converted value in Gram 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 Gram: Step-by-Step Guide

Converting Troy Ounce to Gram involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Troy Ounce = 31.1035 grams

Example Calculation:

Convert 5 troy ounces: 5 × 31.1035 = 155.518 grams

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.

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What is a Troy Ounce and a Gram?

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)

The gram (symbol: g) is a unit of mass equal to exactly one-thousandth of a kilogram (1/1000 kg or 0.001 kg). It's also equal to exactly 1,000 milligrams.

The gram is part of the International System of Units (SI) and is derived from the kilogram, the SI base unit for mass.

Mathematical Relationships

1 gram equals:

1,000 milligrams (mg)
0.001 kilograms (kg)
0.000001 metric tons (tonnes)
0.035274 ounces (oz)
0.00220462 pounds (lb)

Key conversion:

1 ounce = 28.3495 grams (this is the most common gram-to-imperial conversion)

Why Grams?

While the kilogram is the official SI base unit for mass, grams are more practical for everyday measurements:

Perfect for human-scale objects: Most food ingredients, medications, and small items fall naturally into the 1-1000 gram range, avoiding the need for decimal points.

Avoids decimal confusion: "250 grams of flour" is clearer than "0.25 kilograms of flour" for most people.

Universal adoption: Used in 195+ countries for cooking, nutrition labels, postal services, and commerce.

Scientific convenience: Laboratory measurements often use grams for reagents, samples, and specimens.

Historical Water-Based Definition

Original elegance: The gram was originally defined as the mass of 1 cubic centimeter (1 cm³) of pure water at maximum density (approximately 4°C).

Beautiful interconnection:

1 gram of water = 1 cubic centimeter = 1 milliliter
1 kilogram of water = 1 liter = 1,000 cubic centimeters

This made conversions between mass and volume trivial for water, the most common substance on Earth.

Modern definition: Since 2019, the gram is defined through the kilogram, which is now defined by fixing the numerical value of the Planck constant. This ties the gram to fundamental physics constants rather than physical objects or substances.

Note: The Troy Ounce is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Gram belongs to the metric (SI) system.

History of the Troy Ounce and Gram

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.

French Revolution Origins: 1790s

Revolutionary Rationalization: The gram was born from the French Revolution's ambition to replace the chaotic medieval system of weights with a rational, decimal-based system.

Name Etymology: The word "gram" derives from the Late Latin "gramma" (meaning "small weight"), which came from the Greek "grámma" (γράμμα), meaning "letter" or "small weight."

1791: The Water Standard: French scientists defined the gram as the mass of one cubic centimeter (1 cm³) of pure water at its maximum density (approximately 4°C or 39.2°F).

Why water? Water is universally available, easily purified, and has predictable properties. This made the metric system reproducible anywhere in the world without needing reference objects.

April 7, 1795: Official Adoption: France officially adopted the metric system, including the gram as the fundamental unit of small mass measurements.

19th Century: Global Spread

1799: Kilogram Prototype: The French created the Kilogramme des Archives, a platinum cylinder serving as the physical definition of the kilogram (and thus the gram as 1/1000 of it).

1875: Metre Convention: The Treaty of the Metre established international cooperation on measurement standards. Representatives from 17 nations (including the United States) signed the treaty in Paris.

1889: International Prototype Kilogram (IPK): A new platinum-iridium cylinder was crafted and stored in Paris as the world's official kilogram. The gram remained defined as 1/1000 of this artifact.

Scientific Adoption: Throughout the 1800s, scientists worldwide embraced grams for laboratory measurements, making it the standard for chemistry, biology, and physics.

20th Century: Universal Standard

Post-WWII Metrication: After World War II, most countries transitioned to the metric system for trade, science, and daily life. The gram became the global standard for food labeling, recipes, and commerce.

CGS System: The centimeter-gram-second (CGS) system was widely used in physics until the 1960s, elevating the gram to fundamental status in scientific equations.

1960: SI System Established: The International System of Units (SI) formalized the kilogram as the base unit, with the gram as a derived unit (0.001 kg).

2019: The New SI Redefinition

May 20, 2019: Historic Change: The kilogram was redefined based on the Planck constant (a fundamental constant of quantum mechanics) rather than the physical prototype in Paris.

Why the change? The International Prototype Kilogram was losing mass over time (about 50 micrograms per century relative to copies). A definition based on physics constants ensures eternal stability.

Impact on grams: The gram's definition automatically changed to align with the new kilogram definition, now tied to fundamental physics rather than a physical object.

Common Uses and Applications: troy ounces vs grams

Explore the typical applications for both Troy Ounce (imperial/US) and Gram (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 grams

Cooking and Baking Worldwide

European and Global Standard: Outside the United States, recipes almost universally use grams:

"250g flour"
"150g sugar"
"50g butter"
"2g salt"

Precision Baking: Professional bakers worldwide prefer grams because:

Eliminates volume measurement inconsistencies (scooped vs. sifted flour)
Provides repeatable results
Allows accurate scaling (double recipe = double all gram measurements)
Avoids confusion between liquid and dry measures

Kitchen Scales: Digital kitchen scales in metric countries display grams as the primary unit, with tare functions for zeroing containers.

Nutrition and Food Labels

Global Nutrition Facts: Nutrition labels worldwide show values per 100 grams of product:

Energy: calories or kilojoules per 100g
Protein: grams per 100g
Fat: grams per 100g
Carbohydrates: grams per 100g
Sodium: milligrams per 100g

US Nutrition Facts: American labels show grams for macronutrients:

"Serving Size: 28g (about 1 oz)"
"Total Fat 8g"
"Protein 5g"
"Total Carbohydrate 20g"

Dietary Tracking: People counting macros or calories track intake in grams:

Protein goal: 150 grams per day
Carbohydrate limit: 50 grams per day (low-carb diet)
Fat target: 70 grams per day

Scientific and Laboratory Use

Chemistry: Chemical reactions measured in grams:

"Weigh 25.00 grams of sodium chloride"
"Add 5.0 grams of catalyst"
Molar mass expressed as grams per mole (g/mol)

Biology: Biological samples and reagents:

Tissue samples: 100-500 mg (0.1-0.5 grams)
Protein concentration: µg/mL (micrograms per milliliter)
DNA yield: nanograms to micrograms

Physics: Mass measurements in experiments:

Gravitational experiments measure mass in grams
Momentum calculations (kg·m/s, converted from grams)
Density measurements (g/cm³)

Precious Metals and Jewelry

Gold and Silver Trading: Bullion and coins sold by gram weight:

"1g gold bar"
"5g silver round"
"100g gold bullion bar"

Jewelry Manufacturing: Gold and silver priced by weight:

14K gold ring: 4.2 grams × $45/gram = $189
Sterling silver necklace: 15 grams × $0.80/gram = $12

Purity and Karats: Gold content calculated by weight:

18K gold = 75% pure gold by weight
10-gram 18K gold ring contains 7.5 grams pure gold

Fitness and Bodybuilding

Protein Intake: Athletes track daily protein in grams:

Bodybuilder goal: 150-200 grams protein per day
Endurance athlete: 100-120 grams protein per day
General fitness: 1.6-2.2 grams per kilogram body weight

Supplement Servings:

Whey protein powder: 30 grams per scoop
Creatine monohydrate: 5 grams per day
BCAAs: 5-10 grams pre/post workout
Glutamine: 5 grams per serving

Macro Tracking: Fitness apps track grams of protein, carbs, and fat consumed daily.

Drug Dosing and Pharmaceuticals

Medication Doses: Prescriptions specify doses in milligrams (mg) or grams:

"Take 1 gram (1,000mg) of amoxicillin"
"500mg tablet, take two for 1g dose"

Over-the-Counter: OTC medications use grams/milligrams:

Acetaminophen: 500mg per tablet
Maximum daily dose: 4 grams (4,000mg)

Precision Matters: Medication dosing requires extreme precision—confusing grams and milligrams can be fatal (1,000× error).

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.

Conversion Table: Troy Ounce to Gram

Troy Ounce (oz t)	Gram (g)
0.5	15.552
1	31.104
1.5	46.655
2	62.207
5	155.517
10	311.035
25	777.587
50	1,555.174
100	3,110.348
250	7,775.869
500	15,551.738
1,000	31,103.477

How do I convert Troy Ounce to Gram?

To convert Troy Ounce to Gram, 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.

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What is the conversion factor from Troy Ounce to Gram?

The conversion factor depends on the specific relationship between Troy Ounce and Gram. 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 Gram back to Troy Ounce?

Yes! You can easily convert Gram back to Troy Ounce by using the swap button (⇌) in the calculator above, or by visiting our Gram to Troy Ounce converter page. You can also explore other weight conversions on our category page.

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What are common uses for Troy Ounce and Gram?

Troy Ounce and Gram 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.

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All Weight Conversions

Kilogram to Gram Kilogram to Milligram Kilogram to Pound Kilogram to Ounce Kilogram to Stone Kilogram to Ton (metric)Kilogram to Ton (US)Kilogram to Ton (UK)Kilogram to Microgram Kilogram to Carat Kilogram to Slug Kilogram to Troy Ounce Kilogram to Pennyweight Kilogram to Grain Kilogram to Dram Kilogram to Quintal Kilogram to Atomic Mass Unit Kilogram to Pavan (India)Kilogram to Kati (India)Kilogram to Masha (India)Kilogram to Dina (India)Kilogram to Pras (India)Kilogram to Lota (India)Gram to Kilogram Gram to Milligram Gram to Pound Gram to Ounce Gram to Stone Gram to Ton (metric)Gram to Ton (US)Gram to Ton (UK)Gram to Microgram Gram to Carat Gram to Slug Gram to Troy Ounce Gram to Pennyweight Gram to Grain Gram to Dram Gram to Quintal Gram to Atomic Mass Unit Gram to Pavan (India)Gram to Kati (India)Gram to Masha (India)Gram to Dina (India)Gram to Pras (India)Gram to Lota (India)Milligram to Kilogram Milligram to Gram Milligram to Pound Milligram to Ounce Milligram to Stone Milligram to Ton (metric)Milligram to Ton (US)Milligram to Ton (UK)Milligram to Microgram Milligram to Carat Milligram to Slug Milligram to Troy Ounce Milligram to Pennyweight Milligram to Grain Milligram to Dram Milligram to Quintal Milligram to Atomic Mass Unit Milligram to Pavan (India)Milligram to Kati (India)Milligram to Masha (India)Milligram to Dina (India)Milligram to Pras (India)Milligram to Lota (India)Pound to Kilogram Pound to Gram Pound to Milligram Pound to Ounce Pound to Stone Pound to Ton (metric)Pound to Ton (US)Pound to Ton (UK)Pound to Microgram Pound to Carat Pound to Slug Pound to Troy Ounce Pound to Pennyweight Pound to Grain Pound to Dram Pound to Quintal Pound to Atomic Mass Unit Pound to Pavan (India)Pound to Kati (India)Pound to Masha (India)Pound to Dina (India)Pound to Pras (India)Pound to Lota (India)Ounce to Kilogram Ounce to Gram Ounce to Milligram Ounce to Pound Ounce to Stone Ounce to Ton (metric)Ounce to Ton (US)Ounce to Ton (UK)Ounce to Microgram Ounce to Carat Ounce to Slug Ounce to Troy Ounce Ounce to Pennyweight Ounce to Grain Ounce to Dram Ounce to Quintal Ounce to Atomic Mass Unit Ounce to Pavan (India)Ounce to Kati (India)Ounce to Masha (India)Ounce to Dina (India)Ounce to Pras (India)Ounce to Lota (India)Stone to Kilogram Stone to Gram Stone to Milligram Stone to Pound Stone to Ounce

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