⚖️ Weight Unit Converter
How It Works
Type in any field and the rest update instantly (kilogram-based, six decimal places). Anchors worth memorizing: 1 kg ≈ 2.2 lb, 1 oz ≈ 28.35 g, 1 lb = 16 oz ≈ 454 g. Full rules:
- 1 metric ton = 1,000 kg; 1 kg = 1,000 g = 1,000,000 mg
- 1 stone = 14 lb ≈ 6.35 kg (how Brits state body weight: "12 stone" ≈ 76 kg)
- 1 US short ton = 2,000 lb ≈ 907 kg — when a trade document says "ton," always confirm which one
Bake by Weight, Not by Cup
Professional bakers weigh ingredients because volume lies: a "cup of flour" ranges from 120 g (spooned and leveled) to 150 g (scooped and packed) — a 25% swing that ruins bread. Useful equivalents when converting American recipes:
- Butter: 1 US stick = 4 oz ≈ 113 g; an 8 oz block ≈ 227 g.
- Flour: 1 cup all-purpose ≈ 120–125 g by King Arthur's standard.
- Sugar: 1 cup granulated ≈ 200 g; brown sugar packed ≈ 220 g.
- Watch for fluid ounces: "8 fl oz of milk" is volume (237 ml), not weight — don't put it on the scale expecting 227 g (though for water and milk it's close).
The Ounce That Isn't: Troy Weight
Gold, silver, and platinum trade in troy ounces: 1 troy oz = 31.1035 g, about 10% heavier than the everyday (avoirdupois) ounce of 28.35 g. So "gold at $2,400 an ounce" means per 31.1 grams. The pound situation is stranger still — a troy pound is only 12 troy ounces, which is why precious-metal dealers quote ounces and grams, never pounds.
Shipping: When Your Parcel Weighs More Than It Weighs
Couriers charge by the greater of actual weight and dimensional (volumetric) weight — typically length × width × height (cm) ÷ 5000 for international air. A 3 kg box of pillows measuring 60×40×40 cm bills as 19.2 kg. Before comparing courier quotes, convert everything to one unit system (this tool for the weights, our length converter for the dimensions).
Frequently Asked Questions
Is 50 lb the same as 23 kg for baggage?
Almost but not exactly: 50 lb = 22.68 kg, and 23 kg = 50.7 lb. Airlines enforce whichever unit they publish, so pack to the stated unit if you're near the limit.
Why do UK scales show stones?
Body weight in Britain is traditionally quoted in stones and pounds ("11 st 6 lb" = 160 lb ≈ 72.6 kg). Multiply stones by 14 to get pounds, then convert here.
What's the difference between mass and weight?
Physically, kilograms measure mass and weight is a force (newtons). In daily use the words are interchangeable, and scale readings barely vary anywhere on Earth — the conversions here are unaffected.
How precise are the results?
Six decimal places, using exact definition-based factors (1 lb ≡ 453.59237 g since 1959). Precision is limited by your scale, not this converter.