Weight Converter
Convert between weight units including kilograms, pounds, ounces, grams, tons, and stone. Free online converter.
What is Weight Converter?
A weight (mass) converter translates between metric units (milligrams, grams, kilograms, metric tons), imperial units (ounces, pounds, stones, US/UK tons), and other systems like troy ounces for precious metals. Weight conversion comes up in cooking (grams vs ounces), shipping (kilograms vs pounds), fitness (body weight in stones vs kilograms), manufacturing (metric tons vs short tons), and international commerce where products are measured differently in different markets.
How It Works
Enter a weight value and select source and target units. The tool converts through kilograms as the base unit, applying precise conversion factors: 1 pound = 0.45359237 kg, 1 ounce = 28.349523125 grams, 1 stone = 6.35029 kg, etc. It handles the distinction between avoirdupois ounces (everyday use) and troy ounces (precious metals), and between US short tons (2000 lbs) and UK long tons (2240 lbs). Results show appropriate decimal precision for practical use.
Quick Reference
| Metric | Imperial | Conversion |
|---|---|---|
| 1 gram | 0.035 oz | 1 oz = 28.35 g |
| 1 kg | 2.205 lbs | 1 lb = 453.6 g |
| 100 g | 3.527 oz | 1 stone = 6.35 kg |
| 1 metric ton | 2,204.6 lbs | 1 US ton = 907.2 kg |
| 500 g | 1.102 lbs | 1 lb = 16 oz |
Common Use Cases
- •Converting cooking recipe measurements between metric (grams) and imperial (ounces/pounds)
- •Calculating shipping costs by converting package weights between kilograms and pounds
- •Converting body weight between kilograms, pounds, and stones for fitness and medical purposes
- •Translating precious metal prices between troy ounces and grams for investment calculations
- •Converting industrial material weights between metric tons and US/UK tons for trade
- •Translating food nutrition labels between metric and imperial measurements
Frequently Asked Questions
What's the difference between metric and imperial tons?▼
A metric ton is 1000 kg (2204.6 lbs). An imperial ton is 2240 lbs. This tool uses metric tons.
What is the difference between mass and weight?▼
Mass is the amount of matter and does not change with location; weight is the force gravity exerts on that mass. A 70 kg person has the same mass on the Moon but weighs about a sixth as much. Everyday use treats kilograms as a weight, which is technically loose but universally understood.
How many pounds are in a kilogram exactly?▼
One pound is defined as exactly 0.45359237 kilograms, so a kilogram is approximately 2.20462 pounds. The familiar 2.2 shortcut is close enough for cooking but drifts noticeably over large quantities.
What is the difference between a US ton, a UK ton and a metric tonne?▼
A US short ton is 2,000 pounds (907.18 kg), a UK long ton is 2,240 pounds (1,016.05 kg) and a metric tonne is 1,000 kilograms (2,204.6 lb). The three differ by up to 12 percent, which is a costly ambiguity in shipping and commodities.
What is a stone and where is it used?▼
A stone is 14 pounds, or about 6.35 kilograms, and is still the everyday unit for body weight in the UK and Ireland. It is normally written as stones plus pounds, so 11 st 4 lb is 158 pounds or about 71.7 kilograms.
Why do troy ounces differ from ordinary ounces?▼
A troy ounce, used for precious metals, is about 31.103 grams, while the avoirdupois ounce used for everything else is about 28.349 grams — roughly 10 percent lighter. Gold quoted per ounce always means troy ounces, so using the wrong one misprices the metal significantly.
Further Reading
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