Weight Converter 🔒 Your data never leaves your browser.

Convert between mg, g, kg, tonnes, ounces, pounds and stone.

All units

Milligrams
Grams
Kilograms
Metric Tons
Ounces
Pounds
Stone
US Tons

About this tool

A weight converter turns a value in one mass unit into any other, from milligrams up to metric and US tons. Conversions run through a shared grams-based table, so every unit — including imperial oddities like stone — is exact to the underlying multiplication factor rather than a rounded lookup.

Type a value once and see it converted between the two units you pick, plus a full reference table against every other supported unit at the same time. Everything runs locally in your browser; nothing you enter is uploaded.

Frequently asked questions

What's the difference between a metric tonne and a US ton?

A metric tonne is exactly 1,000 kg (2,204.6 lb). A US (short) ton is 2,000 lb (about 907.18 kg) — noticeably lighter. This tool labels the metric option "Metric Tons" and the US option "US Tons" so you don't accidentally mix them up.