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    Weight & Mass Converter

    Convert between milligrams, grams, kilograms, tonnes, ounces, pounds, and stone instantly.

    Free to use. Runs in your browser.

    Enter a weight and select the unit to see conversions to all other weight units.

    Milligrams (mg)

    1,000,000 mg

    Grams (g)

    1,000 g

    Metric Tonnes (t)

    0.001 t

    Ounces (oz)

    35.273991 oz

    Pounds (lb)

    2.204624 lb

    Stone (st)

    0.157473 st

    Three Systems, One Planet

    The metric system uses grams and kilograms. The imperial system uses ounces and pounds. And then there's stone, a unit the rest of the world finds baffling but the UK and Ireland refuse to give up. A British person's weight is in stone and pounds. Their food is sold in grams and kilograms. Their American relatives think in pounds. No wonder everyone needs a converter.

    The key relationships are dead simple: 1 kg = 2.205 lbs. 1 lb = 453.6 g. 1 stone = 14 lbs = 6.35 kg. Every other conversion builds on these three numbers.

    Conversion Quick Reference

    FromToMultiply byExample
    GramsOunces0.03527250 g = 8.82 oz
    OuncesGrams28.34958 oz = 226.8 g
    KilogramsPounds2.204675 kg = 165.3 lbs
    PoundsKilograms0.4536150 lbs = 68.0 kg
    StoneKilograms6.350311 st = 69.9 kg
    KilogramsStone & lbs÷ 6.35 + remainder80 kg = 12 st 8 lbs
    Metric tonnesPounds2,204.61 t = 2,204.6 lbs

    Mental math shortcut: To convert kg to lbs, double the number and add 10%. So 70 kg → 140 + 14 = 154 lbs (exact: 154.3). To go from lbs to kg, halve the number and subtract 10%. 150 lbs → 75 - 7.5 = 67.5 kg (exact: 68.0).

    Body Weight by Unit System

    Your doctor uses kg. Your gym uses lbs. Your nan asks in stone. Here's the same weight in all three:

    Stone & lbsPoundsKilograms
    8 st 0 lbs112 lbs50.8 kg
    9 st 0 lbs126 lbs57.2 kg
    10 st 0 lbs140 lbs63.5 kg
    11 st 0 lbs154 lbs69.9 kg
    12 st 0 lbs168 lbs76.2 kg
    13 st 0 lbs182 lbs82.6 kg
    14 st 0 lbs196 lbs88.9 kg
    15 st 0 lbs210 lbs95.3 kg
    16 st 0 lbs224 lbs101.6 kg

    Practical Weight References

    Numbers without context are meaningless. Here's what different weights actually feel like:

    100g

    A medium apple. 3.5 oz. About the weight of a smartphone without a case.

    500g

    A pack of mince from the supermarket. About 1.1 lbs. Roughly the weight of a hardback book.

    1 kg

    A litre of water. 2.2 lbs. About the weight of a bag of sugar.

    5 kg

    A bag of potatoes. 11 lbs. About the weight of a small cat.

    23 kg

    Standard airline checked bag limit. 50.7 lbs. Roughly the weight of a car tyre.

    Mass vs Weight: Does It Matter?

    Technically, kilograms measure mass (the amount of stuff) and pounds measure force (how hard gravity pulls on that stuff). On Earth's surface, this distinction is irrelevant for everyday purposes, 1 kg always weighs 2.205 lbs.

    It only matters in physics and engineering. On the Moon, a 75 kg person still has 75 kg of mass but would weigh only about 27.5 lbs instead of 165 lbs. For cooking, shipping, fitness, and everything else on this planet, kg and lbs are interchangeable via a fixed conversion factor.

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    How to use this tool

    1

    Enter the weight value you want to convert

    2

    Select the source unit from the dropdown

    3

    View instant conversions to all other weight units

    Common uses

    • Converting recipe ingredients between grams and ounces
    • Calculating luggage weight limits in kg or lbs
    • Converting body weight between imperial and metric
    • Comparing product weights across international listings

    Share this tool

    Frequently Asked Questions

    How many pounds in a kilogram?
    1 kilogram = 2.20462 pounds. A quick shortcut: double the kg and add 10%. So 80 kg ≈ 160 + 16 = 176 lbs (exact: 176.4 lbs).
    How many grams in an ounce?
    1 ounce = 28.3495 grams. This is the avoirdupois ounce used for food and general weighing. A troy ounce (used for precious metals) is 31.1035 grams.
    What is a stone?
    A stone is a UK unit equal to 14 pounds or approximately 6.35 kilograms. It's commonly used for body weight in the UK and Ireland but rarely used elsewhere.
    How do I convert stone to kilograms?
    Multiply stone by 6.35029. For example, 11 stone = 11 × 6.35 = 69.85 kg. To include pounds: convert stone to lbs (× 14), add remaining lbs, then multiply total by 0.4536.
    How many kilograms is 150 pounds?
    150 pounds = 68.04 kilograms. Divide pounds by 2.205 for the conversion, or halve the number and subtract 10% for a quick estimate.
    What is the difference between mass and weight?
    Mass is the amount of matter in an object (measured in kg). Weight is the force of gravity on that mass (measured in newtons). On Earth's surface, the distinction rarely matters for everyday conversions.
    What is a metric tonne?
    A metric tonne is 1,000 kilograms (about 2,205 lbs). It's different from a US short ton (2,000 lbs / 907 kg) and a UK long ton (2,240 lbs / 1,016 kg).
    How many milligrams in a gram?
    There are exactly 1,000 milligrams in a gram. Milligrams are commonly used for medication dosages, supplements, and measuring small quantities of spices.
    What is the luggage weight limit in kg?
    Most airlines allow 23 kg (50.7 lbs) for checked bags and 7-10 kg (15-22 lbs) for carry-ons. Premium tickets often allow 32 kg (70.5 lbs) per checked bag.
    How do I quickly convert lbs to kg?
    Divide by 2.2, or for a rough estimate, halve the number and subtract 10%. Example: 180 lbs ÷ 2 = 90, minus 9 = 81 kg (exact: 81.6 kg).
    What does a troy ounce weigh?
    A troy ounce is 31.1035 grams, about 10% heavier than a regular (avoirdupois) ounce. Gold, silver, and platinum are always measured in troy ounces.
    How heavy is a gallon of water?
    A US gallon of water weighs about 3.785 kg (8.34 lbs). A UK/imperial gallon weighs about 4.546 kg (10.02 lbs). Water's density varies slightly with temperature.

    Results are for general informational purposes only and should be checked before use. They are not professional advice. See our Disclaimer and Terms of Service.