Weight Converter — Free Online Tool

What Is Weight Converter?

A free online weight converter. Convert between milligrams, grams, kilograms, metric tons, ounces, pounds, stones, and US tons. Real-time conversion with a full reference table.

Converting between weight units is a practical need across many contexts — following a recipe that uses grams when your scale measures ounces, tracking fitness progress in kilograms but seeing your gym equipment listed in pounds, or calculating shipping costs in metric tons versus US tons. Weight Converter handles eight units bidirectionally, with a full reference table for easy comparison.

The supported units span both metric and imperial systems: milligrams (mg), grams (g), kilograms (kg), metric tons (t), ounces (oz), pounds (lb), stones (st), and US tons. Enter a value in any unit field and all other fields update in real time. The conversion factors are based on international standards: 1 kilogram equals exactly 2.20462 pounds, 1 stone equals 14 pounds (used for body weight in the UK), and 1 US ton equals 2,000 pounds while 1 metric ton equals 1,000 kilograms.

The swap button reverses the conversion direction, letting you go from imperial to metric and back without re-entering values. This is useful when you have a set of measurements in one system and need the equivalent in another — for example, converting a series of body weights from stones to kilograms or ingredient weights from ounces to grams.

The bidirectional conversion approach means every unit is both an input and an output. You can see how 5 kilograms compares in pounds, ounces, and stones simultaneously. This makes the tool useful not just for single conversions but for understanding the relationships between different weight units at a glance.

Real-World Use Cases for Weight Converter

Converting a Recipe from Metric to Imperial Units

A European recipe calls for 250 grams of flour and 100 grams of butter. Your kitchen scale only measures ounces. Enter 250 in the grams field and see 8.82 ounces. Enter 100 grams to get 3.53 ounces. The real-time conversion lets you check each ingredient quickly.

Tracking Body Weight Using Different Unit Systems

Your fitness tracker shows weight in kilograms (72 kg) but you are used to pounds. Enter 72 in the kilograms field and see 158.73 pounds. If you use stones (UK system), the same value shows as 11 stone 4 pounds. Track progress in whichever unit you prefer.

Calculating Shipping Weight for International Freight

A shipment weighs 500 kilograms for European origin but the US freight company quotes rates per US ton. Enter 500 in the kilograms field and see 0.5 metric tons and 0.55 US tons. Convert to pounds for comparison: 1,102 pounds.

Why Use Weight Converter?

8 units: mg, g, kg, t, oz, lb, st, US ton
Real-time conversion as you type
Full reference table for all units
Swap direction with one click

How to Use Weight Converter — Step by Step

Enter a value in any unit field.

All other units update instantly.

Copy any value with the copy button.

Who Is Weight Converter Best For?

cooking
fitness
shipping
science

Pro Tips for Weight Converter

11 kilogram is approximately 2.2 pounds. For quick mental estimates, double the kilograms and add 10%. For example, 70 kg ≈ 70 × 2.2 = 154 lb.
2The stone unit (14 lb) is primarily used for body weight in the UK and Ireland. Most other countries use kilograms. The US uses pounds.
3When cooking, remember that fluid ounces measure volume, not weight. An ounce of water weighs approximately 1 ounce, but an ounce of flour weighs less. Use weight ounces for dry ingredients.
4For industrial and scientific applications, use metric tons (1,000 kg). For US domestic freight, use US tons (2,000 lb or 907 kg). The tool shows both so you do not confuse them.

Weight Converter — Frequently Asked Questions

How many pounds are in a kilogram?

1 kilogram equals 2.20462 pounds. To convert kg to lb, multiply by 2.20462.

What is a stone?

A stone (st) is a British unit equal to 14 pounds or 6.35029 kilograms. It is commonly used for body weight in the UK.

How accurate are the unit conversions?

Conversions use NIST-standard conversion factors with precision up to 15 significant digits. Currency exchange rates update every 10 minutes from a free data source.

Can I convert between any two units?

Yes. Each converter supports all standard units within its category. For example, the length converter handles metric, imperial, and nautical units.

Is Weight Converter really free to use?

Yes, Weight Converter is completely free with no hidden charges, no usage limits, and no premium tiers. You can use it as often as you need without signing up or providing any personal information.

Ready to Use Weight Converter?

Free online tool — works in your browser, no sign-up required. Start using it right now.

Try It Now