Weight Converter
Convert between kilograms, pounds, ounces, grams, stones, carats, and more weight/mass units — plus a gold & precious metal purity calculator (karat, fineness).
Everyday Uses
Luggage allowances
Airline limit says 23 kg, your bathroom scale reads 47 lb — convert to know if you're packing a problem before the check-in counter does.
International recipes
A British recipe wants 450 g of flour, your kitchen scale shows ounces. Convert precisely — baking is chemistry and rough guesses show.
Gym plates abroad
Traveling and the gym plates are in kilos? Convert your usual working weight so you don't under- or over-load the bar.
Shipping costs
Carriers quote by kg or lb depending on the service — convert your parcel's weight to compare rates fairly.
Airline baggage limits
Allowances are quoted in kg on most airlines and lb on some US carriers. Convert before you get to the desk, not after.
Recipe quantities
European recipes weigh in grams while American ones use pounds and ounces — convert to whichever your scale reads.
Common conversions
Frequently Asked Questions
How many pounds are in a kilogram, and how do you convert between them?
1 kg = 2.20462 lbs. To convert kg to pounds, multiply by 2.205. To convert pounds to kg, multiply by 0.4536 (or divide by 2.205). Quick mental math: double the kg value and add 10% — e.g. 70 kg → 140 + 14 = 154 lbs. Common reference: 1 kg ≈ 2.2 lbs; 100 kg = 220.5 lbs; a 16 lb bowling ball weighs about 7.26 kg.
What is a carat, and how is it different from karat?
Carat (ct) is a unit of mass for gemstones and pearls: 1 carat = 0.2 grams = 200 milligrams exactly, standardised internationally since 1907. Karat (kt) is a completely different concept — it measures gold purity on a 24-point scale, not weight. A "2-carat diamond" describes its mass; an "18-karat ring" describes the gold's purity (75% pure gold). The similar spelling causes frequent confusion, but one is a weight unit and the other is a purity scale.
What is the difference between weight and mass, and does it matter for conversions?
Mass is the amount of matter in an object (kilograms, grams) — it never changes. Weight is the force of gravity on that mass (newtons) — it changes on the Moon or in space. In everyday use "weight" and "mass" are used interchangeably, and kg/lbs conversions treat them the same way. Technically, a 70 kg person weighs 686 newtons on Earth but only 114 N on the Moon (1/6th gravity) — though their mass stays 70 kg.
What is gold karat and fineness, and how do they relate to purity percentage?
Karat (kt) measures gold purity on a 24-point scale where 24kt = 100% pure gold. Fineness expresses the same purity per mille (parts per 1,000) — e.g. 18kt = 750 fineness = 75% pure gold. Common marks: 24kt/999 (fine gold), 22kt/916, 18kt/750, 14kt/585, 10kt/417, 9kt/375. To convert: fineness = karat ÷ 24 × 1000; karat = fineness ÷ 1000 × 24. Sterling silver is marked 925 fineness (92.5% silver); fine silver is 999.
How many ounces are in a pound, and how does the stone unit work?
1 pound = 16 ounces (avoirdupois, the everyday system). 1 stone = 14 pounds = 6.35 kg. The stone is commonly used for body weight in the UK and Ireland. Note: the troy ounce (used for precious metals like gold and silver) ≠ avoirdupois ounce: 1 troy oz = 31.1035 g vs 1 av. oz = 28.3495 g — a 1 oz gold bar is a troy ounce, not a regular ounce, so it weighs about 10% more than you might expect.
How do you convert kilograms to stones and pounds?
Step 1: divide kg by 6.35029 to get stones (with decimal). Step 2: the integer part is stones; multiply the decimal part by 14 to get remaining pounds. Example: 75 kg ÷ 6.35029 = 11.81 stone → 11 stone + (0.81 × 14) = 11 stone 11.3 lbs ≈ 11 st 11 lb. Reverse: (stones × 14 + pounds) × 0.4536 = kg.
What are common weight conversion benchmarks to memorise?
Useful reference weights: 1 oz = 28.35 g. 1 lb = 453.6 g. 1 kg = 2.205 lbs. 1 carat = 0.2 g (a 1-carat diamond fits on a fingertip). 1 troy oz = 31.1 g (a standard gold coin). 1 stone = 6.35 kg. 1 US ton (short ton) = 2,000 lbs = 907.2 kg. 1 metric tonne = 1,000 kg = 2,205 lbs. A standard bag of sugar = 1 kg; a US nickel coin = 5 g; a paperclip ≈ 1 g.