Weight Converter: Kilograms, Pounds, Ounces and More

Every conversion goes through kilograms as the common step: first convert your value to kilograms, then convert kilograms to the target unit.

• Kilograms = value × (kilograms per "from" unit)
• Result = kilograms ÷ (kilograms per "to" unit)

The "kilograms per unit" figures are exact international definitions — for example, one pound is defined as exactly 0.45359237 kg, and one ounce as exactly 0.028349523125 kg.

Convert 1 kg to pounds. Kilograms = 1 × 1 = 1 kg. Pounds = 1 ÷ 0.45359237 = 2.20462 lb. The full table for the same value also shows 1,000 g, 35.274 oz, 0.15747 st and 0.001 t.

One value and two dropdowns are all it takes. The result appears instantly with the target unit highlighted in a full table, so you can compare at a glance.

Step by step

1. Enter the value. Decimals are fine — 2.5 kg works as well as 2500 g.
2. Choose the "from" unit. The unit your number is currently in.
3. Choose the "to" unit. Pounds is preselected, since kg-to-lb is the most common conversion.
4. Press Calculate. Read the headline result, then scan the full table.

Converting length too?

Weight answers "how heavy"; for "how long" or "how far" you need a different set of units entirely. A length converter handles millimetres through miles with the same instant table layout.

Metric units scale by powers of ten — 1,000 grams make a kilogram, 1,000 kilograms make a tonne. Imperial units grew from historical trade measures: 16 ounces make a pound, 14 pounds make a stone.

The eight units compared

Weight and body measurements

Scales in the UK often report body weight in stone and pounds, while most of the world uses kilograms. Health tools standardise on kilograms — a BMI calculator, for example, expects your weight in kg — so this converter is the bridge between your bathroom scale and the health charts.

The converter uses exact definitions (1 lb = 0.45359237 kg) rather than rounded approximations like 0.45, so results stay accurate through chained conversions. Display rounding is separate: large values show 2 decimals, small values show up to 6, which keeps tables readable without hiding precision.

How many decimals do you need?

Authoritative definitions

Unit definitions are maintained by national measurement institutes. The US National Institute of Standards and Technology (NIST) Office of Weights and Measures publishes the reference standards behind the metric–imperial relationships used here.

These are the conversions people look up most often, rounded for quick reading. Use the calculator above for exact values.

Quick reference table

Remembering the direction

The easy mistake is multiplying when you should divide. A quick sanity check helps: a kilogram is heavier than a pound, so kg → lb must give a bigger number (1 → 2.2). If your answer looks backwards — 0.45 lb for 1 kg — you divided instead of multiplying.