Weight Converter
How does weight conversion work?
Weight conversions are commonly needed for cooking, shipping, health and fitness tracking, and international commerce. This converter handles all major weight units in both metric and imperial systems. Key conversions: 1 kg = 2.205 lbs, 1 lb = 16 oz = 453.6g, 1 stone = 14 lbs = 6.35 kg. Need to continue this calculation? Try the Length Converter or the Ideal Weight Calculator.
Common Weight Conversions
For health and fitness: body weight is typically measured in kg (metric) or lbs (imperial). For cooking: ingredients are measured in grams or ounces. For shipping: packages are measured in kg or lbs, with heavy cargo in metric tons.
What should you check before converting units?
Conversions are simple, but accuracy depends on using the correct unit. Always check whether the value is metric, imperial, digital, or temperature-based before comparing results. For work, study, travel, recipes, or shopping, round only at the end so the final number stays more accurate. If a result will be used for safety, construction, medicine, or finance, confirm it with an official standard or professional source.
Who finds this calculator most useful?
This converter is useful for travel, recipes, study, product comparison, engineering notes, online shopping, and daily measurements. It is especially helpful when two sources use different systems, such as metric and imperial units.
How does this calculator help in real situations?
The Weight Converter is built for people who want a fast answer without losing context. It keeps the calculation simple, shows the result clearly, and helps you understand what the number means before you use it in a real decision.
Conversion tools help translate values between measurement systems quickly. They are especially useful when comparing products, recipes, travel details, technical values, or international information.
What is the difference between weight and mass?
Technically, weight is the force exerted on an object by gravity (measured in Newtons), while mass is the amount of matter in an object (measured in kilograms). In everyday use, "weight" is used to mean mass — what a scale measures. A person "weighing" 70 kg has a mass of 70 kg; their weight (force) would be approximately 686 Newtons on Earth's surface. This guide covers mass conversion, which is what most people need for practical daily purposes.
Complete weight/mass conversion reference
- 1 kilogram (kg) = 1,000 grams = 2.20462 pounds = 35.274 ounces = 0.157473 stone
- 1 gram (g) = 1,000 milligrams = 0.001 kg = 0.035274 ounces
- 1 milligram (mg) = 0.001 grams (used in medicine and nutrition labelling)
- 1 pound (lb) = 16 ounces = 453.592 grams = 0.453592 kg
- 1 ounce (oz) = 28.3495 grams = 0.0625 pounds
- 1 stone (UK) = 14 pounds = 6.35029 kg (used for body weight in the UK and Ireland)
- 1 tonne (metric ton) = 1,000 kg = 2,204.62 pounds = 1.10231 short tons
- 1 short ton (US ton) = 2,000 pounds = 907.185 kg
Common everyday weight conversion scenarios
Body weight: global health records use kilograms. US and UK fitness apps often use pounds or stone. 75 kg = 75 × 2.20462 = 165.35 pounds = 11 stone 11.35 pounds.
Cooking and baking: global recipes typically specify grams; many Western recipes use ounces and cups. 200 grams flour = 200 × 0.035274 = 7.05 ounces. 1 pound butter = 453.59 grams.
Parcel shipping: Courier rates are calculated by actual weight (kg) or volumetric weight. International shipping often requires converting to pounds for US-based carriers.
Precious metals: Gold and silver are traded in troy ounces (different from avoirdupois ounces). 1 troy ounce = 31.1035 grams. 10 grams of gold = 10 ÷ 31.1035 = 0.3215 troy ounces.
Nutrition labels: Serving sizes and nutrient content are specified in grams and milligrams. 100 grams of food contains 5 grams of fat means fat is 5% by weight.
Traditional global weight measurements
Before metrication, India used traditional weight units that are still referenced in some contexts:
- Tola: 11.664 grams — historically used for gold and silver; still referenced in some gold jewellery pricing (10 grams = 0.857 tola; a common gold unit is "10 grams" which replaced the traditional "1 tola" of 11.664g)
- Maund (Mann): Approximately 37.32 kg — used for agricultural produce in historical contexts
- Seer: Approximately 933 grams — fractional unit of the maund
- Quintal: 100 kg — still used in agricultural commodity trading
Weight in medicine — why precision matters
Drug doses, especially for children, are calculated by body weight in kilograms (mg per kg of body weight). A dosing error caused by confusing pounds with kilograms can result in a dose 2.2× higher or lower than intended. Always confirm whether a medical weight specification uses kilograms or pounds. The WHO standard for pharmaceutical dosing is kilograms.
Stone: the uniquely British weight unit
1 stone = 14 pounds = 6.35 kg. Used for body weight in the UK and Ireland. A person weighing 11 stone 7 lbs weighs 73 kg or 161 lbs. The stone is not used in the US, Canada, Australia, or any metric country — it is exclusively a UK/Irish body weight convention. UK bathroom scales often display in stone and pounds; international scales in kg.
Troy ounces vs avoirdupois ounces: precious metals and everyday weight
Everyday ounce (avoirdupois): 28.35 grams. 16 oz = 1 pound. Troy ounce (precious metals): 31.10 grams — about 10% heavier. Gold, silver, platinum, and other precious metals are always quoted in troy ounces. When the gold price is "$2,300 per ounce," that is per troy ounce, not the regular ounce. This distinction matters for anyone buying or selling bullion.
Frequently asked questions about weight conversion
How many kg is 1 pound? Exactly 0.45359237 kg (commonly rounded to 0.454 kg or 0.45 kg). To convert pounds to kg, divide by 2.205. To convert kg to pounds, multiply by 2.205.
What is stone used for? Stone is used for human body weight in the United Kingdom and Ireland. 1 stone = 14 pounds = 6.35 kg. A person "weighing 12 stone 4 pounds" = (12 × 14) + 4 = 172 pounds = 78.0 kg.
Is a metric ton the same as a regular ton? No. A metric tonne = 1,000 kg. A short ton (US) = 2,000 pounds = 907.2 kg. A long ton (UK) = 2,240 pounds = 1,016 kg. When "tonne" is written with an "e", it refers to the metric version.
How many pounds are in a kilogram, and what is a stone in kg?
| Unit | Kilograms | Pounds | Ounces | Grams |
|---|---|---|---|---|
| 1 milligram (mg) | 0.000001 | 0.0000022 | 0.0000353 | 0.001 |
| 1 gram (g) | 0.001 | 0.002205 | 0.03527 | 1 |
| 1 ounce (oz) | 0.02835 | 0.0625 | 1 | 28.35 |
| 1 pound (lb) | 0.4536 | 1 | 16 | 453.6 |
| 1 kilogram (kg) | 1 | 2.2046 | 35.274 | 1,000 |
| 1 stone (st) | 6.3503 | 14 | 224 | 6,350 |
| 1 metric tonne (t) | 1,000 | 2,204.6 | 35,274 | 1,000,000 |
| 1 US short ton | 907.2 | 2,000 | 32,000 | 907,185 |
| 1 UK long ton | 1,016 | 2,240 | 35,840 | 1,016,047 |
Common body weights in kg, pounds, and stone
| Kilograms | Pounds | Stone & Pounds |
|---|---|---|
| 50 kg | 110.2 lbs | 7 st 12 lbs |
| 60 kg | 132.3 lbs | 9 st 6 lbs |
| 70 kg | 154.3 lbs | 11 st 0 lbs |
| 80 kg | 176.4 lbs | 12 st 8 lbs |
| 90 kg | 198.4 lbs | 14 st 2 lbs |
| 100 kg | 220.5 lbs | 15 st 10 lbs |
| 120 kg | 264.6 lbs | 18 st 13 lbs |
Sources & References
Sources: BIPM SI Brochure 9th edition — kilogram definition (Planck constant); NIST Special Publication 811 — Guide for SI; UK Weights and Measures Act 1985 (stone definition).
Traditional Indian weight units: tola, ser, and maund
Before metrification, India used a system of traditional weight units that still appear in gold jewellery pricing, agricultural markets, and older property documents:
| Traditional Unit | Region | Grams | Modern Equivalent |
|---|---|---|---|
| Tola | All India (especially gold) | 11.664 g | Used for gold pricing (1 tola = 10 masha) |
| Ratti / Rati | North India | 0.1215 g | Gemstone weight |
| Masha | North India | 0.972 g | 1/10th of a tola |
| Ser / Seer | North India | 933.1 g | ≈ 1 kg |
| Maund / Man | All India | 37,324 g | 40 sers ≈ 37.3 kg |
| Pao | Maharashtra, Bengal | 233.3 g | Quarter of a seer |
| Chatank | Bengal, Bihar | 58.3 g | 1/16th of a seer |
Gold in India is still quoted per 10 grams and per tola. 1 tola = 11.664 g; 1 kg = 85.73 tola.
Troy weight vs avoirdupois: why gold uses different units
Gold and silver are measured in troy ounces (oz t), not the standard (avoirdupois) ounce. 1 troy ounce = 31.1035 grams, compared to 1 avoirdupois ounce = 28.3495 grams. Gold price in USD/troy oz can be converted: price per gram = ($/oz t) ÷ 31.1035. At $2,000/troy oz: ₹price per gram (at ₹83/USD) = (2000 × 83) ÷ 31.1035 = ₹5,337/gram. The London Bullion Market Association (LBMA) and MCX India both price gold in troy ounces.