Weight Converter
Convert instantly between metric and imperial weight units.
How to Use
- Enter a value and choose the unit you're converting from.
- Choose the unit you want to convert to.
- The result updates instantly as you type — there's no Convert button to press.
- Use the swap button to reverse the conversion direction.
Formula
value_in_target_unit = value × (from_unit_to_kilograms ÷ to_unit_to_kilograms). Every unit converts through kilograms as the common base, so no conversion pair needs its own hard-coded formula.
Worked Example
Convert 1 pound to kilograms.
- 1 pound equals exactly 0.45359237 kilograms.
- 0.45359237 kilograms ÷ 1 (kilograms per kilogram) = 0.45359237
Result: 0.45359237 kg
Conversion Table
| Unit | Symbol |
|---|---|
| Milligrams | mg |
| Grams | g |
| Kilograms | kg |
| Metric Tonnes | t |
| Ounces | oz |
| Pounds | lb |
| Stone | st |
About This Tool
What this tool does
Converts a weight or mass value between metric units (milligrams, grams, kilograms, metric tonnes) and imperial/US units (ounces, pounds, stone).
When to use it
Use it whenever you need to translate a weight between metric and imperial — reading a recipe, checking luggage or parcel weight limits, following a body-weight or fitness target, or converting a shipping or product spec.
What the result means
The result is the equivalent weight in the target unit, rounded to a readable number of decimal places without losing meaningful precision.
Assumptions & limitations
All imperial conversion factors use the exact international avoirdupois definitions agreed in 1959 (1 pound = 0.45359237 kg exactly; 1 ounce = 1⁄16 pound; 1 stone = 14 pounds), not rounded approximations, so results stay accurate however many times a value is converted back and forth.