Stone to Dram Converter

Convert stones to drams with our free online weight converter.

Quick Answer

1 Stone = 3584 drams

Formula: Stone × conversion factor = Dram

Use the calculator below for instant, accurate conversions.

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

Stone to Dram Calculator

How to Use the Stone to Dram Calculator:

  1. Enter the value you want to convert in the 'From' field (Stone).
  2. The converted value in Dram will appear automatically in the 'To' field.
  3. Use the dropdown menus to select different units within the Weight category.
  4. Click the swap button (⇌) to reverse the conversion direction.
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How to Convert Stone to Dram: Step-by-Step Guide

Converting Stone to Dram involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Stone = 3584 drams

Example Calculation:

Convert 5 stones: 5 × 3584 = 17920 drams

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.

What is a Stone and a Dram?

1 stone = 14 avoirdupois pounds (lb) = 6.35029318 kilograms (kg) EXACT

The stone (symbol: st) is a unit of mass in the Imperial system, legally defined in terms of pounds, which are themselves defined in terms of kilograms. The exact conversion is:

1 pound = 0.45359237 kilograms (international definition, 1959)
1 stone = 14 × 0.45359237 kg = 6.35029318 kg

Stone and Pounds Notation

The stone is almost never used alone for body weight. Instead, it's combined with additional pounds:

Format: "X stone Y pounds" or "X st Y lb"

Examples:

  • 10 st 0 lb = 10 stone exactly = 140 lb = 63.5 kg
  • 10 st 7 lb = 10 stone + 7 pounds = 147 lb = 66.7 kg
  • 12 st 3 lb = 12 stone + 3 pounds = 171 lb = 77.6 kg

Why this format? It provides precision without unwieldy decimal places. Saying "10.5 stone" is rare—people say "10 stone 7" instead (10 stone + 7 pounds = 10.5 stone).

Stone vs. Kilogram vs. Pound

Three systems for measuring body weight:

| System | Unit | Used In | Precision | |-----------|----------|-------------|---------------| | Imperial (UK) | Stone + Pounds | UK, Ireland | "11 st 7 lb" (161 lb) | | Imperial (US) | Pounds only | United States, Canada | "161 lb" | | Metric | Kilograms | Most of the world | "73 kg" |

Cultural difference:

  • Americans say "I weigh 161 pounds"
  • British say "I weigh 11 stone 7" (rarely "161 pounds")
  • Europeans say "I weigh 73 kilograms"

Why 14 Pounds?

The number 14 has no scientific basis—it's purely historical. Medieval England used base-12 counting (duodecimal) for some systems:

  • 12 inches = 1 foot
  • 12 pence = 1 shilling (pre-1971)
  • But 14 pounds = 1 stone (not 12!)

Theory: The 14-pound wool stone emerged from trade practices. A "sack of wool" weighed 364 pounds = 26 stones (26 × 14 = 364), a convenient round number for taxation and commerce.

Avoirdupois Dram (Commercial)

The avoirdupois dram is defined in the common weight system used for most goods:

Relationships:

  • 1 dram = 1/16 ounce (avoirdupois)
  • 1 dram = 1/256 pound (avoirdupois)
  • 1 dram = 27.34375 grains (exactly)
  • 1 dram ≈ 1.7718451953125 grams (exactly)

Symbol: dr, dr av, or dr avdp

Historical use: General commerce, precious materials, spices, ammunition powder charges.

Apothecary/Troy Dram (Pharmaceutical)

The apothecary dram (also called drachm) belongs to the apothecaries' weight system used historically in pharmacy:

Relationships:

  • 1 dram (ʒ) = 1/8 ounce (apothecary)
  • 1 dram = 3 scruples
  • 1 dram = 60 grains (exactly)
  • 1 dram ≈ 3.8879346 grams (exactly)

Symbol: ʒ (resembles the number 3, representing 3 scruples)

Historical use: Compounding medicines, pharmaceutical measurements, medical prescriptions.

The Critical Difference

Apothecary dram = 2.194 × Avoirdupois dram

This 2.2× ratio causes confusion. Historical recipes and medical texts must specify which system they use, or dosages could be dangerously incorrect.

Fluid Dram (Volume, Not Weight)

Adding to the confusion, the fluid dram is a unit of volume:

Fluid dram (imperial):

  • 1/8 fluid ounce (imperial)
  • ≈ 3.5516 mL

Fluid dram (US):

  • 1/8 fluid ounce (US)
  • ≈ 3.6967 mL

Symbol: fl dr, fl ʒ, or ℈

This is completely separate from weight drams, though historically related (1 fluid dram of water weighs approximately 1 avoirdupois dram).

Note: The Stone is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Dram belongs to the imperial/US customary system.

History of the Stone and Dram

Ancient and Medieval Origins (Pre-1300)

The concept of standardized stones: Before precise metallic weights, communities used stones as trade counterweights. A merchant would keep a reference stone in the marketplace, verified by local authorities, against which goods were weighed.

Advantages:

  • Durability: Stones don't corrode or wear like metal
  • Availability: Every village had stones
  • Tamper-resistance: Hard to secretly shave weight off a stone

Problem: Every region had different stones! The "stone of wool" in Yorkshire differed from the "stone of wool" in Kent.

Medieval Standardization Attempts (1300-1824)

Edward III's wool stone (1340): King Edward III standardized the wool stone at 14 pounds as part of regulating the lucrative wool trade (England's economic backbone in the Middle Ages). The "sack of wool" was defined as 364 pounds = 26 stones.

Commodity-specific stones: Different goods had different stone weights:

| Commodity | Stone Weight | Reasoning | |--------------|-----------------|---------------| | Wool | 14 lb (6.35 kg) | Trade standard | | Meat | 8 lb (3.63 kg) | Butcher's stone | | Glass | 5 lb (2.27 kg) | Fragile goods | | Cheese | 16 lb (7.26 kg) | Agricultural products | | Iron | Variable (8-15 lb) | Regional differences |

Why different weights? Practical reasons:

  • Heavy commodities (iron, lead): Smaller stone weight made counting easier
  • Light, valuable goods (wool, spices): Larger stone weight reduced fractions
  • Tradition: Each guild jealously guarded its customary weights

The Weights and Measures Act 1824

The problem: By 1800, Britain had dozens of incompatible stone definitions, creating chaos in trade and taxation.

The solution: The 1824 Act standardized British weights and measures:

  • 14 pounds = 1 stone (for general use, not tied to specific commodities)
  • Stone officially defined in relation to the pound
  • Commodity-specific stones discouraged (but not banned)

Imperial standardization: The Act also defined:

  • 1 pound = 7,000 grains
  • 16 ounces = 1 pound
  • 14 pounds = 1 stone
  • 8 stone = 1 hundredweight (112 pounds)
  • 20 hundredweight = 1 ton (2,240 pounds)

Body weight adoption: The Victorian era (1837-1901) saw the stone become the standard for human weighing. Bathroom scales, medical records, and public health data used stones and pounds.

Metrication and Persistence (1965-Present)

The Weights and Measures Act 1965: The UK officially adopted the metric system, making kilograms the legal unit for trade. However, the Act exempted personal weighing—bathroom scales could continue showing stones.

Why the exemption?

  • Cultural resistance: Brits refused to abandon stones for body weight
  • Economic lobbying: Scale manufacturers didn't want to retool
  • Medical inertia: NHS records already used stones; conversion would be costly

The result: 60+ years later, the stone persists:

  • Bathroom scales: Default to stones in the UK (even modern digital ones)
  • NHS medical records: Still record patient weight in stones/pounds
  • Weight loss programs: Slimming World, Weight Watchers UK use stones
  • Media: British newspapers report celebrity weight in stones
  • Sports: Boxing, horse racing, rowing use stones for weight classes

Ireland's experience: Ireland officially adopted metric units in 2005, but the stone remains common for body weight, especially among older generations.

Generational divide:

  • Older Brits (60+): Think exclusively in stones
  • Middle-aged (30-60): Bilingual (stones and kilograms)
  • Younger (<30): Increasingly use kilograms, but still understand stones

Cultural Tenacity

The stone is the most persistent Imperial unit in British daily life, outlasting:

  • Fahrenheit: Replaced by Celsius (weather, ovens)
  • Inches/feet for height: Partially replaced by metres (though feet still common)
  • Pints: Milk sold in litres (though beer still sold in pints!)
  • Miles: Road signs still use miles (the UK never fully switched)

Why the stone survives:

  1. Emotional connection: Body weight is personal; changing units feels invasive
  2. Convenient range: For adults, weight is 8-20 stones (easy to remember vs. 50-127 kg)
  3. Medical exemption: Doctors use stones, so patients use stones
  4. Social reinforcement: Everyone around you uses stones, so you do too

Ancient Greek Drachma (600 BCE - 300 CE)

The drachma coin: Greek city-states minted silver coins called drachmas, weighing approximately 4.3 grams (varying by region and period).

Origin of name: "Drachma" (δραχμή) derives from "drax" (handful) or "drassomai" (to grasp), possibly referring to a handful of six obol coins.

Weight standard: The Attic drachma (Athens) weighed about 4.3 g of silver, becoming a widespread weight and monetary standard.

Roman Adoption (300 BCE - 500 CE)

Drachma in Roman medicine: Roman physicians adopted Greek medical practices, including pharmaceutical measurements based on the drachma.

Galen's formulations: The physician Galen (129-216 CE) used drachmas extensively in medicinal recipes, establishing the unit in medical tradition.

Byzantine and Islamic Medicine (500-1200 CE)

Byzantine continuation: The Eastern Roman Empire (Byzantium) preserved Greek medical texts, maintaining the drachm as a pharmaceutical unit.

Islamic Golden Age: Arab physicians (Al-Razi, Avicenna) translated Greek medical works, incorporating drachms into Arabic pharmacy. The dirham (Arabic coin) shares the same etymological root.

Transmission to Europe: Through Islamic Spain and Sicily, Arabic medical knowledge returned to Western Europe (11th-13th centuries), bringing pharmaceutical drachm measurements.

Medieval European Apothecaries (1200-1600)

Apothecary guilds: European cities established apothecary guilds, standardizing medicinal weights based on the drachm.

The apothecary system:

  • 1 pound (lb ap) = 12 ounces
  • 1 ounce (℥) = 8 drams (ʒ)
  • 1 dram = 3 scruples (℈)
  • 1 scruple = 20 grains (gr)

Result: 1 apothecary dram = 60 grains

Symbol evolution: The symbol ʒ (scribal abbreviation for Latin "drachma") became standard for the dram.

British Standardization (1600-1800)

London Pharmacopoeia (1618): The first official British pharmacopoeia standardized apothecary weights, including the dram at 60 grains.

Avoirdupois emergence: Simultaneously, the avoirdupois system developed for general commerce, creating a different dram:

  • Avoirdupois dram = 1/16 ounce = 27.34375 grains

Coexistence: Two dram standards coexisted—apothecary for medicine, avoirdupois for trade.

American Adoption (1776-1900)

U.S. Pharmacopeia (1820): The first U.S. Pharmacopeia codified pharmaceutical measurements, adopting British apothecary standards including the dram.

Medical education: American medical schools taught apothecary measurements. Physicians wrote prescriptions using symbols like ʒ for drams.

Commercial use: Avoirdupois drams measured gunpowder, spices, precious materials, and other commodities.

Ammunition Application (1800s-Present)

Black powder charges: Early firearms used black powder measured in drams. A "3-dram load" meant 3 avoirdupois drams of powder.

Dram equivalent: With the transition to smokeless powder (1880s onward), manufacturers created "dram equivalent" ratings—the amount of smokeless powder producing the same velocity as a given dram measure of black powder.

Modern shotshells: Today's shotgun shells still reference "3 dram equivalent" or "3¼ dram equivalent" on the box, though actual powder weights are in grains or grams.

Metrication and Decline (1900-Present)

British pharmacy (1970): The UK officially abandoned apothecary weights, switching entirely to metric (grams, milligrams).

American pharmacy (1970s-1980s): U.S. pharmacy schools phased out apothecary measurements, adopting metric. By 1990, nearly all prescriptions used metric units.

Persistence:

  • Ammunition: Dram equivalent ratings continue
  • Historical recipes: Antique cookbooks and medical texts
  • Collectors: Antique apothecary scales and weights

Common Uses and Applications: stones vs drams

Explore the typical applications for both Stone (imperial/US) and Dram (imperial/US) to understand their common contexts.

Common Uses for stones

1. Body Weight Measurement

The stone is the unit for body weight in the UK and Ireland.

Bathroom scales:

  • Display: "11 st 7 lb" (digital) or analog dial with stone markings
  • Dual units: Many scales toggle between st/lb and kg
  • Default: Stones for UK-sold scales, even from international brands

Weighing yourself:

  • British: "I'm 12 stone 3"
  • American: "I'm 171 pounds"
  • European: "I'm 78 kilograms"

Weight goals:

  • "I want to lose a stone" = 14-pound goal
  • "I'm aiming for 10 stone" = target weight
  • "I've gained half a stone" = 7-pound increase

2. Medical and Healthcare

NHS patient records: British hospitals and GPs record weight in stones/pounds (with kg conversion).

Medical forms:

  • Pre-op questionnaires: "Weight: __ st __ lb"
  • Prescription dosing: Sometimes based on weight (converted to kg for calculations)
  • Anesthesia planning: Weight in stones converted to kg for drug dosages

Maternity care:

  • Booking appointment: "What was your pre-pregnancy weight?" (stones)
  • Pregnancy weight tracking: "You've gained 2 stone, which is healthy"
  • Post-natal: "Most women lose 1-2 stone in the first weeks"

Mental health context: Eating disorder treatment tracks weight changes in stones (e.g., anorexia recovery: "gained 1 stone to 7 stone 10").

3. Weight Loss and Fitness

Slimming clubs:

  • Slimming World, Weight Watchers UK: Weigh-ins in stones
  • Awards: "Half-stone hero," "Stone club," "3-stone milestone"
  • Targets: "Lose 10% of body weight" (e.g., 1.5 stone from 15 stone start)

Fitness apps (UK versions):

  • MyFitnessPal UK: Input weight in stones
  • Fitbit/Garmin: UK users set goals in stones
  • Weight tracking graphs: Y-axis shows stones, not kg

Personal trainers: British trainers discuss client progress in stones: "You've dropped from 14 stone to 12 stone 8—fantastic!"

4. Sports Weight Classes

Boxing: British boxing traditionally used stones for weight classes (now officially kilograms, but stones still common in commentary).

Horse racing:

  • Jockey weights: Includes jockey + saddle + lead weights to meet required "riding weight"
  • Handicapping: Horses carry different weights (in stones) to equalize competition
  • Penalties: "Carrying 9 stone 7" vs. "Carrying 10 stone" affects race outcomes

Rowing: Lightweight rowers must weigh under certain stone limits (now metric, but historically stones).

5. Everyday Conversation

The stone pervades British informal speech:

Common phrases:

  • "I'm 11 stone, give or take" = approximate weight
  • "She must be 10 stone soaking wet" = very light
  • "He's put on a stone since Christmas" = seasonal weight gain
  • "I haven't been 9 stone since I was 15!" = nostalgic reference

Social etiquette:

  • It's impolite to ask someone's weight directly, but acceptable to discuss your own
  • Women might say "I'm trying to get back to 9 stone" (goal weight)

6. Media and Entertainment

British TV shows:

  • Reality TV: "Love Island" contestants' weights discussed in tabloids (stones)
  • Medical shows: "Embarrassing Bodies" references patient weight in stones
  • Game shows: "The Biggest Loser UK" tracked loss in stones

Newspapers and magazines:

  • Celebrity weight speculation: "Has she lost 2 stone?"
  • Health articles: "How to lose half a stone by summer"
  • Success stories: "I lost 8 stone and transformed my life!"

7. Historical and Cultural References

Literature: Victorian novels reference weight in stones:

  • Dickens, Austen rarely mention specific weights (impolite)
  • 20th-century literature: "She was a strapping girl of 12 stone"

British humor: Comedians joke about weight in stones:

  • "I'm not overweight, I'm just undertall for my 14 stone!"

Generational markers:

  • Older Brits: "When I got married, I was 8 stone"
  • Modern comparison: "That's only 112 pounds—too thin by today's standards!"

When to Use drams

1. Ammunition and Reloading

Shotshell ratings: Manufacturers mark shotgun shells with "dram equivalent" to indicate approximate velocity/power level.

Why still used? Tradition and familiarity. Shooters understand "3 dram load" means standard power, while "3¾ dram" is heavy magnum.

Reloading manuals: Some reloading data references dram equivalents alongside modern grain measurements.

2. Historical Recipe Interpretation

19th-century cookbooks: Recipes may call for "1 dram of nutmeg" or "2 drams of ginger."

Conversion challenge: Must determine if the recipe uses avoirdupois or apothecary drams (usually avoirdupois for cooking).

Modern equivalent: 1 avoirdupois dram ≈ 1.77 grams ≈ 1/3 teaspoon (for dry spices)

3. Antique Apothecary Items

Collectible scales: Antique apothecary scales often have dram weights marked with ʒ.

Medicine bottles: Historical pharmacy bottles may indicate contents in drams.

Historical research: Understanding drams is essential for interpreting 18th-19th century medical texts.

4. Pharmaceutical History

Old pharmacopoeias: Historical pharmaceutical formulas use apothecary drams.

Example prescription (1850s): "℞ Quinine sulfate ʒij" = Take 2 drams of quinine sulfate

Modern interpretation: 2 apothecary drams = 7.78 grams

Additional Unit Information

About Stone (st)

1. How many pounds are in a stone?

Exactly 14 pounds.

This is a defined constant. There are no regional variations—1 stone always equals 14 pounds in any context.

Calculation examples:

  • 5 stone = 5 × 14 = 70 pounds
  • 12 stone = 12 × 14 = 168 pounds
  • 0.5 stone = 0.5 × 14 = 7 pounds

2. Is the stone used outside the UK and Ireland?

Rarely. The stone is almost exclusive to the UK and Ireland.

Usage by country:

  • UK: Dominant for body weight (even with official metrication)
  • Ireland: Common, especially among older generations
  • Canada, Australia, New Zealand: Not used (fully metric)
  • United States: Not used (pounds only)
  • Rest of world: Not used (metric)

Exception: British expats abroad sometimes use stones, and international weight loss forums may reference stones when discussing UK participants.

3. Why is it called a stone?

Historical practice: Actual stones were used as standardized weights in medieval markets.

How it worked:

  1. A community selected a reference stone of agreed weight
  2. The stone was kept in the marketplace (sometimes literally built into a wall)
  3. Merchants used the reference stone on balance scales to verify weights
  4. Different stones existed for different commodities (wool stone, meat stone, etc.)

Modern name: The unit name "stone" is a fossil of this practice, long after actual stones stopped being used.

4. How do you convert stone to kilograms?

Formula:

Kilograms = Stone × 6.35029318

Quick approximation:

Kilograms ≈ Stone × 6.35 (good to 3 decimal places)

Examples:

  • 10 stone × 6.35 = 63.5 kg
  • 12 stone × 6.35 = 76.2 kg
  • 15 stone × 6.35 = 95.25 kg

Online tools: Most conversion sites and apps include stone ↔ kilogram calculators.

5. How do British people talk about their weight?

Typical format: "I'm X stone Y pounds" or "I'm X stone Y"

Examples:

  • "I'm 11 stone 7" = 11 stone + 7 pounds = 161 lb = 73 kg
  • "I'm just over 12 stone" = slightly more than 168 lb
  • "I'm nearly 10 stone" = approaching 140 lb

Rarely said:

  • "I'm 11.5 stone" (uncommon—people say "11 stone 7" instead)
  • "I'm 161 pounds" (too American—Brits don't think in pounds alone)
  • "I'm 73 kilograms" (used by younger generations, but less common)

Conversational weight: Discussing weight is somewhat taboo, so people often avoid specifics: "I need to lose a bit of weight" rather than "I need to drop from 13 to 11 stone."

6. Do British bathroom scales show kilograms?

Yes, most modern scales show both.

Typical features:

  • Default: Stones and pounds (st/lb)
  • Toggle button: Switch to kilograms
  • Dual display: Some show both simultaneously

Older scales: Analog scales from before 2000 often show stones only.

Buying scales in the UK: Even international brands (Fitbit, Garmin) sell UK-specific versions that default to stones.

7. Will the UK ever stop using stones?

Unlikely in the near future.

Reasons for persistence:

  1. Cultural attachment: Body weight is personal; people resist change
  2. Legal exemption: Personal weighing scales exempt from trade regulations
  3. NHS inertia: Changing medical records costly
  4. Generational use: Older generations use stones exclusively
  5. No enforcement: No push to mandate kilograms for personal use

Trend: Younger Brits (under 30) increasingly use kilograms, especially those who travel or use fitness apps with international audiences. However, the stone will likely persist for decades among older populations.

Comparison: Similar to Fahrenheit in the US—officially discouraged but culturally entrenched.

8. What is a "half stone"?

Half stone = 7 pounds = 3.175 kg

Usage:

  • Weight loss: "I've lost half a stone" = 7 lb loss
  • Weight gain: "I've put on half a stone over Christmas" = 7 lb gain
  • Milestones: "Half-stone club" in weight loss programs

Why significant? Half a stone is a noticeable weight change—enough to affect how clothes fit and how you feel, but achievable in 3-7 weeks of dieting (at 1-2 lb/week loss).

9. How do you write stone and pounds?

Common formats:

Formal:

  • "11 stone 7 pounds"
  • "11 st 7 lb"

Informal:

  • "11 stone 7"
  • "11st 7lb" (no spaces)
  • "11-7" (very casual, context-dependent)

Avoid:

  • "11.7 stone" (ambiguous—could mean 11 stone 7 lb or 11 stone 9.8 lb)
  • "11/7 st" (confusing notation)

Medical records: NHS typically uses "st/lb" format: "Patient weight: 12 st 3 lb"

10. Why do Americans not use stone?

The United States never adopted the stone for body weight.

Historical reasons:

  1. Colonial divergence: By the time the stone standardized in Britain (1824), the US had already established pounds as the body weight unit
  2. Decimal preference: Americans favored simpler base-10 systems where possible
  3. No cultural push: No equivalent to UK's Victorian-era adoption of stones for weighing people

Result: Americans think in pounds only:

  • "I weigh 180 pounds" (no stones)
  • Weight loss: "I lost 30 pounds" (not "2 stone 2 pounds")

Canadian note: Canada officially metricated in the 1970s and uses kilograms, not stones or pounds (though older Canadians may still think in pounds).

11. Is stone a legal unit?

Yes, in the UK and Ireland, but with restrictions.

Legal status:

  • Personal use: Fully legal (bathroom scales, self-weighing)
  • Trade: Must use metric (kilograms) for selling goods by weight
  • Medical: Allowed in patient records (NHS uses stones)

Weights and Measures Act: Kilograms are the legal unit for commerce, but stones remain legal for "non-trade" purposes (personal weighing, medical records).

Comparison: Similar to miles on UK road signs—officially metric, but exceptions preserve traditional units in specific contexts.

12. How much is a stone in other historical weight units?

Stone in troy and apothecary systems:

Troy weight (precious metals):

  • 1 stone (avoirdupois) = 14 pounds (avoirdupois)
  • 1 pound (avoirdupois) = 7,000 grains
  • 1 stone = 98,000 grains (troy)
  • 1 troy pound = 5,760 grains
  • 1 stone ≈ 17.01 troy pounds

Apothecaries' weight (pharmacy):

  • Same grain as troy and avoirdupois (64.79891 mg)
  • 1 stone = 98,000 grains (apothecaries')

Why this matters: Historically, pharmacists used apothecaries' weights, so understanding stone conversions was important for dosing medicines based on body weight.

About Dram (dr)

How many drams are in an ounce (avoirdupois)?

Exactly 16 avoirdupois drams = 1 avoirdupois ounce.

This is the definition:

  • 1 oz av = 16 dr av
  • 1 dr av = 1/16 oz av = 0.0625 oz

How many grams are in a dram (avoirdupois)?

1 avoirdupois dram = 1.7718451953125 grams (exactly).

Practical approximation: 1 dr av ≈ 1.77 g

Derivation: 1 pound av = 453.59237 grams (exact) 1 pound = 256 drams 1 dram = 453.59237 ÷ 256 = 1.77185 g

Is a dram a unit of mass or volume?

Both exist, which causes significant confusion:

Mass (weight):

  • Avoirdupois dram (dr): 1.772 g
  • Apothecary dram (ʒ): 3.888 g

Volume:

  • Fluid dram (fl dr, US): 3.697 mL
  • Fluid dram (fl dr, imperial): 3.552 mL

Context matters:

  • Pharmacy/medicine historically: could be either (check symbols)
  • General commerce: usually weight
  • Modern usage: rare except ammunition (weight-related rating)

What's the difference between avoirdupois and apothecary drams?

Avoirdupois dram (commercial):

  • 1/16 ounce avoirdupois
  • 27.34375 grains
  • 1.772 grams
  • Used for general goods

Apothecary dram (pharmaceutical):

  • 1/8 ounce apothecary
  • 60 grains
  • 3.888 grams
  • Used for medicines

Key difference: Apothecary dram is 2.19× heavier than avoirdupois dram.

What does the symbol ʒ mean?

The symbol ʒ represents the apothecary dram.

Origin: Scribal abbreviation of Latin "drachma" or "dragma."

Appearance: Resembles a fancy number "3," which is appropriate since 1 dram = 3 scruples.

Usage: Historical pharmaceutical prescriptions: "℞ Morphine ʒi" = Take 1 dram of morphine

What is a dram equivalent in ammunition?

"Dram equivalent" is a velocity/power rating for shotgun shells, not actual powder weight.

Historical context: Black powder shotgun loads used actual drams of powder (e.g., "3 drams of black powder").

Modern meaning: A "3 dram equivalent" smokeless powder load produces approximately the same muzzle velocity as a historical 3-dram black powder load.

Actual powder weight: Modern "3 dram equivalent" loads typically contain 18-22 grains of smokeless powder (less than 1 actual dram by weight).

Rating scale:

  • 2¾ dram eq: Light/target
  • 3 dram eq: Standard
  • 3¼ dram eq: Magnum
  • 3¾ - 4 dram eq: Heavy magnum

Do doctors still use drams?

No, modern medicine uses metric units exclusively.

Historical use: 19th and early 20th century physicians wrote prescriptions using apothecary measurements including drams (ʒ).

Transition:

  • UK: Abandoned apothecary units in 1970
  • US: Phased out 1970s-1990s

Current practice: All modern prescriptions use milligrams (mg), grams (g), and milliliters (mL). Drams are historical artifacts.

How do I convert historical dram measurements?

Step 1: Identify the system

  • Pharmacy/medicine: Likely apothecary dram (3.888 g)
  • Cooking/commerce: Likely avoirdupois dram (1.772 g)

Step 2: Check for symbols

  • ʒ symbol: Definitely apothecary
  • "dr" or no symbol: Context-dependent (probably avoirdupois for cooking)

Step 3: Convert to grams

  • Avoirdupois: drams × 1.772
  • Apothecary: drams × 3.888

Step 4: Convert to modern measure

  • Grams to teaspoons (dry ingredients): ~5 g per tsp
  • Grams to milliliters (liquids): depends on density

Can I still buy dram weights?

Yes, as antique collectibles, but not for practical use.

Antique apothecary weights: Available from antique dealers, often brass or bronze, marked with ʒ symbol.

Modern equivalents: Not manufactured. Use gram scales instead.

Collectible value: Complete sets of 18th-19th century apothecary weights command $100-500+ depending on condition.

Why did pharmacy abandon drams?

Multiple reasons drove metrication:

1. International standardization: Metric system adopted globally for science and medicine.

2. Safety: Multiple dram systems (avoirdupois vs. apothecary) created dangerous confusion.

3. Ease of calculation: Decimal metric system simpler than fractional apothecary system.

4. Precision: Milligrams allow more precise dosing than grains/scruples/drams.

Result: By 1990, virtually all pharmacy worldwide used metric exclusively.

Conversion Table: Stone to Dram

Stone (st)Dram (dr)
0.51,792
13,584
1.55,376
27,168
517,920
1035,840
2589,600
50179,200
100358,400
250896,000
5001,792,000
1,0003,584,000

People Also Ask

How do I convert Stone to Dram?

To convert Stone to Dram, enter the value in Stone 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 Stone to Dram?

The conversion factor depends on the specific relationship between Stone and Dram. 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 Dram back to Stone?

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

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What are common uses for Stone and Dram?

Stone and Dram 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.

All Weight Conversions

Kilogram to GramKilogram to MilligramKilogram to PoundKilogram to OunceKilogram to StoneKilogram to Ton (metric)Kilogram to Ton (US)Kilogram to Ton (UK)Kilogram to MicrogramKilogram to CaratKilogram to SlugKilogram to Troy OunceKilogram to PennyweightKilogram to GrainKilogram to DramKilogram to QuintalKilogram to Atomic Mass UnitKilogram 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 KilogramGram to MilligramGram to PoundGram to OunceGram to StoneGram to Ton (metric)Gram to Ton (US)Gram to Ton (UK)Gram to MicrogramGram to CaratGram to SlugGram to Troy OunceGram to PennyweightGram to GrainGram to DramGram to QuintalGram to Atomic Mass UnitGram 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 KilogramMilligram to GramMilligram to PoundMilligram to OunceMilligram to StoneMilligram to Ton (metric)Milligram to Ton (US)Milligram to Ton (UK)Milligram to MicrogramMilligram to CaratMilligram to SlugMilligram to Troy OunceMilligram to PennyweightMilligram to GrainMilligram to DramMilligram to QuintalMilligram to Atomic Mass UnitMilligram 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 KilogramPound to GramPound to MilligramPound to OuncePound to StonePound to Ton (metric)Pound to Ton (US)Pound to Ton (UK)Pound to MicrogramPound to CaratPound to SlugPound to Troy OuncePound to PennyweightPound to GrainPound to DramPound to QuintalPound to Atomic Mass UnitPound 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 KilogramOunce to GramOunce to MilligramOunce to PoundOunce to StoneOunce to Ton (metric)Ounce to Ton (US)Ounce to Ton (UK)Ounce to MicrogramOunce to CaratOunce to SlugOunce to Troy OunceOunce to PennyweightOunce to GrainOunce to DramOunce to QuintalOunce to Atomic Mass UnitOunce 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 KilogramStone to GramStone to MilligramStone to PoundStone to Ounce

Verified Against Authority Standards

All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.

NIST Mass and Force Standards

National Institute of Standards and TechnologyUS standards for weight and mass measurements

ISO 80000-4

International Organization for StandardizationInternational standard for mechanics quantities

Last verified: December 3, 2025