Enter a value in any mass unit and instantly see the equivalent in kilograms, pounds, ounces, tonnes, stones and more.
| Unit | Value |
|---|
Mass and weight units split sharply between the metric and imperial worlds — a US recipe in ounces, a shipping label in kilograms, a body weight in stones, a lab sample in milligrams. This tool lets you enter a value once and see it converted to every common mass unit at the same time, from milligrams up to metric tons, without hunting for a specific from/to pair.
Every mass unit converts through the kilogram (kg), the SI base unit of mass. To convert from unit A to unit B:
All mass units are linear multiples of the kilogram, so every conversion here is straightforward multiplication or division — mass has no offset scales the way temperature does.
| Unit | Symbol | Value in Kilograms |
|---|---|---|
| Milligram | mg | 0.000001 |
| Gram | g | 0.001 |
| Kilogram | kg | 1 |
| Metric Ton | t | 1,000 |
| Grain | gr | 0.00006479891 |
| Ounce | oz | 0.028349523125 |
| Pound | lb | 0.45359237 |
| Stone | st | 6.35029318 |
| US Ton (short) | US ton | 907.18474 |
| UK Ton (long) | UK ton | 1,016.0469088 |
| Atomic Mass Unit | u | 1.66053906660 × 10⁻²⁷ |
Note: grain, ounce, pound and stone use the international avoirdupois definitions (exact, 1959 agreement). The US short ton (2,000 lb) and UK long ton (2,240 lb) are different units — check which one a source means before assuming "ton".
Example 1 — Kilograms to Pounds
A 70 kg person: 70 ÷ 0.45359237 kg/lb ≈ 154.32 lb.
Example 2 — Ounces to Grams
An 8 oz steak: 8 × 28.349523125 g/oz ≈ 226.8 g.
Example 3 — Pounds to Stones
A body weight of 168 lb: 168 ÷ 14 lb/st = 12 stone exactly, since 1 stone is defined as 14 lb.
Example 4 — Metric Tons vs US/UK Tons
A shipment listed as 10 metric tons: 10,000 kg ÷ 907.18474 kg/US ton ≈ 11.02 US tons, or ÷ 1,016.0469088 kg/UK ton ≈ 9.84 UK tons — three different "tons" for the same 10,000 kg.