Stone to Quintal Converter
Convert stones to quintals with our free online weight converter.
Quick Answer
1 Stone = 0.063503 quintals
Formula: Stone × conversion factor = Quintal
Use the calculator below for instant, accurate conversions.
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Stone to Quintal Calculator
How to Use the Stone to Quintal Calculator:
- Enter the value you want to convert in the 'From' field (Stone).
- The converted value in Quintal 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 Stone to Quintal: Step-by-Step Guide
Converting Stone to Quintal involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Stone = 0.0635029 quintalsExample Calculation:
Convert 5 stones: 5 × 0.0635029 = 0.317515 quintals
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.
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Need to convert to other weight units?
View all Weight conversions →What is a Stone and a Quintal?
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.
The quintal (symbol: q) is a unit of mass equal to 100 kilograms (220.462 pounds) in the metric system. The term derives from Arabic qinṭār (قنطار), itself from Latin centenarius ("containing a hundred"), reflecting its fundamental definition as "a hundred units" of mass.
The Metric Quintal (100 kg)
The modern metric quintal is precisely defined as:
- 100 kilograms (exact)
- 0.1 metric tons (tonnes)
- 100,000 grams
- 220.462 pounds (avoirdupois)
This standardized definition emerged from France's adoption of the metric system (1795-1799), where the quintal was redefined as exactly 100 kg, replacing the pre-revolutionary quintal of 48.95 kg (100 livres).
Historical Quintal Variants
Before metrication, numerous regional quintal definitions existed:
- French quintal (pre-1795): 48.95 kg (100 livres poids de marc)
- Spanish quintal (quintal castellano): 46.01 kg (100 libras)
- Portuguese quintal: 58.75 kg (4 arrobas)
- Egyptian qinṭār: 44.93 kg (100 raṭls)
- British quintal: 112 pounds (50.80 kg, equivalent to 1 hundredweight)
- Venetian cantaro: 47.66 kg
- Dutch centenaar: 49.4-50.2 kg (varied by city)
- Mexican quintal: 46.01 kg (Spanish colonial)
These variations made international trade complex, contributing to the 19th-20th century push toward metric standardization.
The Quintal in Agricultural Trade
The quintal's strength lies in its practical scale for bulk commodity trade:
- 1 quintal = 2 standard grain bags (50 kg each)
- 10 quintals = 1 metric ton (clean decimal conversion)
- Human-manageable scale: 100 kg is within the range two workers can handle
- Intermediate unit: Bridges small-scale sacks and large-scale tonnage
In commodity markets, prices are often quoted per quintal for crops like wheat, rice, coffee, sugar, and cotton.
Note: The Stone is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Quintal belongs to the imperial/US customary system.
History of the Stone and Quintal
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:
- Emotional connection: Body weight is personal; changing units feels invasive
- Convenient range: For adults, weight is 8-20 stones (easy to remember vs. 50-127 kg)
- Medical exemption: Doctors use stones, so patients use stones
- Social reinforcement: Everyone around you uses stones, so you do too
The quintal's 1,300-year journey from Islamic trade networks to modern agricultural markets reflects the evolution of international commerce and measurement standardization.
Arabic Origins (7th-9th Centuries)
The quintal traces to the Arabic qinṭār (قنطار), borrowed from Latin centenarius ("hundred-weight") or Greek kentenarion (κεντηνάριον). During the Islamic Golden Age (750-1258 CE), Arab merchants dominated Mediterranean, Red Sea, and Indian Ocean trade routes, establishing the qinṭār as a standard for trading spices, grain, textiles, and metals.
The qinṭār typically equaled 100 raṭls (رطل), with the raṭl varying by region from 380-550 grams, making historical qinṭārs range from 38-55 kg. Baghdad's Abbasid Caliphate standardized the qinṭār for taxation and trade regulation around 100 raṭls of approximately 400-450 grams each.
Medieval European Adoption (11th-15th Centuries)
Crusader contact, Venetian trade monopolies, and Reconquista Spain brought Islamic measurement units into European commerce. The quintal entered Romance languages:
- Italian: quintale
- Spanish: quintal
- Portuguese: quintal
- French: quintal
- Catalan: quintar
Each region adapted the concept to their local pound (livre, libra, lira), creating dozens of quintal variants. Venice's cantaro (47.66 kg) dominated Mediterranean spice trade, while Iberian quintals (46-59 kg) became colonial standards in the Americas.
Colonial Spread (16th-18th Centuries)
Portuguese and Spanish colonial expansion exported quintal standards to:
- Latin America: Spanish quintal (46 kg) for silver, cacao, sugar
- Brazil: Portuguese quintal (58.75 kg) for sugar, coffee, gold
- Philippines: Spanish quintal for rice, hemp, sugar (until 1906)
- Goa and Macau: Portuguese quintal in Indian and Chinese trade
These colonial quintals persisted long after independence, with Brazil using the Portuguese quintal until adopting the metric version in the mid-20th century.
French Metric Quintal (1795-1799)
The French Revolution's measurement reform created the metric system, redefining the quintal as exactly 100 kilograms on December 10, 1799 (19 Frimaire, Year VIII).
This represented a radical simplification:
- Old French quintal: 48.95 kg (100 livres poids de marc)
- New metric quintal: 100 kg (100,000 grams)
- Decimal elegance: 10 quintals = 1 ton; 1 quintal = 100 kg = 100,000 g
The metric quintal provided a convenient intermediate unit between the kilogram and the tonne (1,000 kg), ideal for agricultural commerce.
International Adoption (19th-20th Centuries)
The Treaty of the Metre (May 20, 1875) established the International Bureau of Weights and Measures (BIPM) and promoted metric standardization. The 100 kg quintal spread through:
European Metrication:
- Italy (1861 unification): Adopted metric quintal for grain markets
- Germany (1872): Zentner (50 kg) preferred over quintal
- Spain (1852, enforced 1880): Spanish quintal → metric quintal
- Portugal (1852, enforced 1866): Portuguese quintal → metric quintal
Colonial and Post-Colonial Adoption:
- India (1947): British hundredweight replaced by metric quintal
- Pakistan (1947): Adopted metric quintal for wheat, rice, cotton
- Bangladesh (1971): Inherited Pakistani metric quintal
- Francophone Africa (1960s): French colonies adopted metric quintal
- Brazil (mid-20th century): Portuguese quintal → metric quintal
Agricultural Commodity Exchanges:
- Chicago Board of Trade (1848-present): US hundredweight (100 lb, 45.36 kg)
- Brazilian coffee markets (early 20th century): Adopted 60 kg bags (0.6 quintals)
- Indian wheat mandis (markets): Quintals standard by 1950s-1960s
Modern Usage (20th-21st Centuries)
Today, the metric quintal remains active in:
- South Asia: India, Pakistan, Bangladesh use quintals for grain prices
- Latin America: Brazil for coffee/sugar, Argentina for grain
- France and Francophone regions: Agricultural statistics, farm sales
- Mediterranean: Parts of Italy, Spain, Portugal in rural markets
- Africa: Former French colonies (Senegal, Ivory Coast, Mali)
Anglo-American markets largely abandoned the quintal for:
- Metric ton (1,000 kg) in international trade
- US hundredweight (100 lb = 45.36 kg) in American markets
- British hundredweight (112 lb = 50.80 kg) until full metrication (1990s)
Common Uses and Applications: stones vs quintals
Explore the typical applications for both Stone (imperial/US) and Quintal (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 quintals
Agricultural Commodity Trading
The quintal is the standard unit for pricing and trading bulk agricultural products in many markets:
Indian Agricultural Markets (Mandis):
- Wheat prices quoted in rupees per quintal (₹/quintal)
- Rice, cotton, sugarcane traded by quintal
- Government Minimum Support Price (MSP) set per quintal
- Example: Wheat MSP 2023-24 = ₹2,125 per quintal (~$25.50/quintal)
Brazilian Coffee Market:
- Coffee traded in 60 kg bags (0.6 quintals) or full quintals
- Brazilian Real per quintal (@) pricing
- São Paulo commodity exchange quotes
French Agricultural Statistics:
- Crop yields reported in quintaux per hectare (q/ha)
- Wheat: 65-75 q/ha typical yield
- Corn: 80-100 q/ha modern varieties
- Vineyards measured by hectoliters, grain by quintals
Farm Production Records
Farmers track yields, sales, and inventory in quintals where traditional:
- Harvest tallies: "We harvested 450 quintals of wheat from 10 hectares"
- Storage management: "Warehouse capacity 2,000 quintals"
- Sales records: "Sold 120 quintals at ₹2,000/quintal = ₹240,000"
- Seed calculations: "Need 8 quintals of seed for 40 hectares" (20 kg/hectare)
Government Agricultural Policy
Governments use quintals for agricultural planning:
- India's Food Corporation: Procures millions of quintals for public distribution
- Minimum Support Prices: Guaranteed prices per quintal
- Crop insurance: Coverage based on quintals per hectare yields
- Export quotas: "Allow export of 5 million quintals of wheat"
- Buffer stock targets: "Maintain 100 million quintal strategic reserve"
Food Processing Industry
Processing plants measure intake and output in quintals:
- Sugar mills: Sugarcane crushed measured in quintals, sugar recovery percentage calculated
- Rice mills: Paddy intake in quintals, milled rice output (60-70% recovery)
- Flour mills: Wheat processed per day (e.g., 500 quintals/day capacity)
- Coffee roasters: Green coffee beans purchased by quintal
Commodity Futures and Contracts
Agricultural futures markets use quintals in some regions:
- Indian commodity exchanges (MCX, NCDEX): Contracts in quintals
- European grain markets: Tonnes preferred, but quintals used in conversion
- Contract specifications: "Wheat futures: 10 quintals per contract"
Historical and Cultural Contexts
The quintal appears in:
- Historical trade records: Colonial shipping manifests, customs documents
- Literature: Portuguese, Spanish, French novels mentioning quintal prices
- Traditional farming: Multi-generational farms in Mediterranean Europe
- Legal disputes: Land productivity measured in quintals per hectare for valuation
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:
- A community selected a reference stone of agreed weight
- The stone was kept in the marketplace (sometimes literally built into a wall)
- Merchants used the reference stone on balance scales to verify weights
- 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:
- Cultural attachment: Body weight is personal; people resist change
- Legal exemption: Personal weighing scales exempt from trade regulations
- NHS inertia: Changing medical records costly
- Generational use: Older generations use stones exclusively
- 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:
- Colonial divergence: By the time the stone standardized in Britain (1824), the US had already established pounds as the body weight unit
- Decimal preference: Americans favored simpler base-10 systems where possible
- 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 Quintal (q)
How many kilograms are in a metric quintal?
There are exactly 100 kilograms in 1 metric quintal. This is the internationally standardized definition adopted after the French Revolution (1799) and now used in agriculture worldwide.
How does a quintal relate to a metric ton?
1 metric ton (tonne) = 10 quintals. Since 1 tonne = 1,000 kg and 1 quintal = 100 kg, the conversion is a simple decimal shift. This makes quintals ideal for intermediate-scale agricultural measurements.
Is a quintal always 100 kg?
In modern usage, yes—the metric quintal is always 100 kg. However, historically no—pre-metric quintals ranged from 40-120 kg depending on region:
- Spanish: 46 kg
- Portuguese: 58.75 kg
- French (pre-1795): 48.95 kg
- British: 50.8 kg (112 lb) Always check context and date when encountering quintals in historical documents.
Why do Indian farmers use quintals instead of kilograms or tons?
The quintal offers a practical middle scale for farm operations:
- Too small: Tracking thousands of kilograms is cumbersome (5,000 kg vs. 50 quintals)
- Too large: Tons are too big for small farmer transactions (5 tons sounds massive vs. 50 quintals)
- Manageable numbers: Most harvests range 20-100 quintals per hectare (easy mental math)
- Traditional: India adopted quintals during metrication (1947-1960s), now culturally ingrained
- Government policy: Minimum Support Prices quoted per quintal, making it standard
What is the difference between a quintal and a hundredweight?
Metric quintal = 100 kg = 220.462 lb US hundredweight (cwt) = 100 lb = 45.36 kg British hundredweight (cwt) = 112 lb = 50.80 kg
A metric quintal is 2.2× heavier than US cwt and 1.97× heavier than British cwt. The names both mean "hundred," but refer to different base units (metric kg vs. imperial pounds).
How do you convert quintals per hectare to bushels per acre?
Step-by-step for wheat (1 bushel ≈ 27.22 kg at 60 lb/bushel):
-
Convert quintals/ha to kg/ha: Multiply by 100
- 50 q/ha = 5,000 kg/ha
-
Convert kg to bushels: Divide by 27.22 kg/bushel
- 5,000 kg ÷ 27.22 = 183.7 bushels
-
Convert hectares to acres: Divide by 2.47 acres/ha
- 183.7 bushels/ha ÷ 2.47 = 74.4 bushels per acre
Quick formula: q/ha × 0.367 ≈ bushels/acre (for wheat)
Are quintals used in the United States?
Very rarely. The US agricultural sector uses:
- Bushels for grain (wheat, corn, soybeans)
- US hundredweight (100 lb) for livestock, potatoes
- Pounds or tons (2,000 lb) for most commodities
- Metric tons for international trade
Quintals might appear in international trade documents, Latin American imports, or historical contexts, but are not part of standard US agricultural commerce.
Why is Brazilian coffee measured in 60 kg bags instead of quintals?
The 60 kg bag (0.6 quintals) became the Brazilian coffee standard due to:
- Historical Portuguese quintal: 58.75 kg ≈ 60 kg (close approximation)
- Human handling: 60 kg is about the maximum two workers can comfortably lift
- International standard: The 60 kg bag became global coffee standard adopted by other producers
- Convenient: 1,000 kg = 16.67 bags (close to 17), making mental math easier than 10 quintals
Brazilian coffee is thus priced per "saca" (60 kg bag), though sometimes converted to quintals for comparison.
How much wheat is 100 quintals in bushels?
100 quintals = 367 bushels (for wheat at 60 lb/bushel):
- 100 quintals = 10,000 kg = 22,046 pounds
- 22,046 lb ÷ 60 lb/bushel = 367.4 bushels
Alternatively:
- 10,000 kg ÷ 27.22 kg/bushel = 367.4 bushels
This represents about 15.3 acres of excellent wheat yield (24 bushels/acre × 15.3 = 367 bushels).
Do European countries still use quintals today?
Yes, but declining. Usage varies by country:
Still Common:
- France: Agricultural statistics (rendements en quintaux/hectare)
- Italy: Rural markets, traditional farming (quintale)
- Spain/Portugal: Some rural areas, older generation
- Francophone Africa: Senegal, Ivory Coast, Mali
Largely Replaced:
- Germany: Zentner (50 kg) or metric tons preferred
- UK: Fully metricated to kilograms/tonnes (1990s-2000s)
- Netherlands/Nordics: Kilograms and tonnes exclusively
Trend: Urban, industrial, and export sectors use metric tons; rural and traditional markets retain quintals.
What does "yield of 50 quintals per hectare" mean?
50 q/ha means:
- 5,000 kilograms per hectare (50 × 100 kg)
- 5 metric tons per hectare
- 2.02 metric tons per acre (÷ 2.47 acres/ha)
- 4,454 pounds per acre
Context:
- Wheat: 50 q/ha is a good yield (global average ~35 q/ha)
- Corn: 50 q/ha is low (modern varieties reach 100+ q/ha)
- Rice: 50 q/ha is moderate (high-yield areas reach 70+ q/ha)
How do I convert a price from quintals to metric tons?
Multiply by 10 (since 1 metric ton = 10 quintals):
Example 1 - Indian Wheat:
- ₹2,125 per quintal × 10 = ₹21,250 per metric ton
Example 2 - French Grain:
- €25 per quintal × 10 = €250 per metric ton
Example 3 - Brazilian Sugar:
- R$120 per quintal × 10 = R$1,200 per metric ton
Reverse (tons to quintals): Divide by 10
- $500/tonne ÷ 10 = $50 per quintal
Conversion Table: Stone to Quintal
| Stone (st) | Quintal (q) |
|---|---|
| 0.5 | 0.032 |
| 1 | 0.064 |
| 1.5 | 0.095 |
| 2 | 0.127 |
| 5 | 0.318 |
| 10 | 0.635 |
| 25 | 1.588 |
| 50 | 3.175 |
| 100 | 6.35 |
| 250 | 15.876 |
| 500 | 31.752 |
| 1,000 | 63.503 |
People Also Ask
How do I convert Stone to Quintal?
To convert Stone to Quintal, 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.
Learn more →What is the conversion factor from Stone to Quintal?
The conversion factor depends on the specific relationship between Stone and Quintal. 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 Quintal back to Stone?
Yes! You can easily convert Quintal back to Stone by using the swap button (⇌) in the calculator above, or by visiting our Quintal to Stone converter page. You can also explore other weight conversions on our category page.
Learn more →What are common uses for Stone and Quintal?
Stone and Quintal 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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Other Weight Units and Conversions
Explore other weight units and their conversion options:
- Kilogram (kg) • Stone to Kilogram
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- Pound (lb) • Stone to Pound
- Ounce (oz) • Stone to Ounce
- Ton (metric) (t) • Stone to Ton (metric)
- Ton (US) (ton) • Stone to Ton (US)
- Ton (UK) (long ton) • Stone to Ton (UK)
- Microgram (µg) • Stone to Microgram
- Carat (ct) • Stone 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: February 19, 2026