Weight & Mass Unit Converter
Convert between kilograms, grams, pounds, ounces, stones and metric tonnes — metric and imperial mass units.
All conversions route through kilograms using exact factors (1 lb = 0.45359237 kg by definition). Quick ones: 1 kg ≈ 2.205 lb, 1 lb ≈ 454 g, 1 oz ≈ 28.35 g, 1 stone = 14 lb. Note 'mass' (kg, what these measure) differs from 'weight' (force) in physics, though everyday usage treats them as the same.
Formula
About Weight & Mass Unit Converter
The weight converter translates between every common mass unit — kilograms, grams, pounds, ounces, stones and metric tonnes — covering the metric/imperial gaps that come up in cooking, shipping, fitness, travel and trade. Enter a value, pick the units, and get an exact result computed through kilograms using the internationally defined factors (1 pound = exactly 0.45359237 kg). Whether you're reading a foreign scale, converting a recipe, checking baggage limits, or tracking body weight across systems, it removes the awkward arithmetic and the half-remembered conversion factors.
How to use Weight & Mass Unit Converter
- 1Enter your values into Weight & Mass Unit Converter — sensible, domain-typical defaults are pre-filled so you see a real result immediately.
- 2The result recomputes live using the formula shown on the page; there is no button to press.
- 3Adjust any input to compare scenarios, then read the worked example to see the substituted numbers.
Why use Weight & Mass Unit Converter?
- ✓Computes Weight & Mass Unit Converter instantly in your browser — no sign-up, no upload, no server round-trip.
- ✓100% free and unlimited, with the exact formula shown: convert via kilograms: 1 lb = 0.4536 kg exactly.
- ✓Runs entirely client-side, so every value you enter stays private on your device.
- ✓Live recompute as you type, with a worked example and authoritative references for trust.
Frequently asked questions
How do I convert kg to pounds?+
Multiply kilograms by 2.20462 (or divide by 0.45359237). So 70 kg ≈ 154.3 lb, 100 kg ≈ 220.5 lb. A quick estimate: double the kg and add 10% (70 → 140 + 14 = 154). To go from pounds to kg, divide by 2.205 or multiply by 0.4536.
What is a stone in pounds and kilograms?+
1 stone = 14 pounds = 6.35 kg. The stone is still common in the UK and Ireland for body weight — someone who is '11 stone 4' is 11×14 + 4 = 158 lb ≈ 71.7 kg. This converter handles stones directly, and you can convert a stone value to kg or lb to read British weights.
What's the difference between mass and weight?+
In physics, mass (kilograms) is the amount of matter, while weight is the force gravity exerts on it (newtons), so your weight changes on the Moon but your mass doesn't. Everyday language and these units treat them as the same — kg and lb measure mass — which is fine on Earth where gravity is constant.
How many grams in an ounce?+
1 ounce (avoirdupois) = 28.3495 grams, and 16 ounces = 1 pound. For cooking, it's often rounded to 28 g. Note the troy ounce used for precious metals is different (31.1 g) — this converter uses the standard avoirdupois ounce for everyday weights, food and shipping.
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