Weight Converter
Weight Converter — runs in your browser. Inputs are not stored.
Weight unit converter
Enter values, then press Calculate.
The base unit is the kilogram (kg). 1 lb = 0.45359237 kg.
How to use
- Choose a Value and a Unit. The default is 1 kilogram.
- Units are kilogram, gram, milligram, metric ton (t), pound, ounce, stone, short ton (US ton), and long ton (UK ton).
- Press Convert, or change value or unit, and every unit updates.
- Metric ton and US/UK tons are listed separately, so check the wording on trade documents.
- Reset restores 1 kg. Calculation runs only on this device.
Key concepts
Weight (mass) conversion is based on the kilogram. 1 lb = 0.45359237 kg, 1 oz = 0.028349523125 kg, 1 stone = 6.35029318 kg. A metric ton t is 1000 kg. A short ton (US) is about 907.18 kg and a long ton (UK) about 1016.05 kg, so the same word “ton” is not the same value. The table updates as soon as you change value or unit. Milligrams can appear in exponential form for tiny values. Stone is still used for body weight in the UK.
In physics, weight is a force (newtons) and mass is kg, but everyday and logistics conversion uses the same number. This tool converts mass units and does not correct for gravity. Use other converters for length and power. If you do not check whether a shipping document’s ton is metric or short, tens of kilograms can be wrong. This screen lists the three tons side by side to reduce confusion. Volume and length are not covered.
Example
1 kg is 1000 g, about 2.2046 lb, and about 35.274 oz. 1 metric ton is 1000 kg, about 2204.6 lb. The same “ton” is about 907 kg for 1 US short ton and about 1016 kg for 1 UK long ton. To see body weight in stone, read the stone row. 70 kg is about 154.3 lb and about 11.0 st. A 500 g pack is 0.5 kg, about 17.64 oz. 1 US ton of cargo is about 0.907 metric tons.
Related: Length converter · Unit converter
Frequently asked questions
What is the kg–pound factor in the weight converter?
1 lb = 0.45359237 kg. 1 kg is about 2.204622621 lb. That is the definition used in international trade. International air baggage is usually kg; some US domestic contexts use lb. Compare the same number on the two rows.
What is the difference between a metric ton, a US ton, and a UK ton?
t (metric) is 1000 kg. A US ton (short ton) is 2000 lb; a UK ton (long ton) is 2240 lb. They appear as three rows. Short tons are common in US bulk; long tons appear on older British shipping documents. Only the metric ton is close to SI.
Are ounce oz and stone st included?
Yes. An ounce is 1/16 of a pound and a stone is 14 pounds. They are used for body weight and ingredients in the US and UK. Cooking ounces and gold ounces differ. The oz in this table is the avoirdupois ounce.
Do you distinguish mass and weight?
No. These are everyday mass units. If you need newtons (force), use the force type in an engineering unit converter. If a scale shows newtons, use a force converter. The numbers here are mass.
Can I convert grams and milligrams too?
Yes. g and mg are in the list. For small values such as reagents or nutrition facts, read the milligram row. Nutrition mg and cargo t share one table, so watch the scale.
Is the weight I entered left on a server?
No. Multiply and divide run only in the browser and are not stored. Sensitive weighing values are not left in this site’s logs.
Last reviewed: 2026-09-04