Weight & Mass Converter

The international avoirdupois pound is legally defined as exactly 0.45359237 kilograms. One pound consists of 16 ounces, making an avoirdupois ounce equal to exactly 28.349523125 grams. In the United States, a short ton is defined as 2,000 pounds, while a metric tonne is 1,000 kilograms (approximately 2,204.62 pounds).

1 lb = 0.45359237 kg (exact) | 1 oz = 28.349523125 g (exact) | 1 US ton = 2,000 lb

Verified Conversion Examples

Postal Parcel: 2.5 Pounds to Ounces and Grams

Weighing a small parcel for postage and customs declaration.

Calculation:2.5 lb × 16 oz/lb = 40 oz; 2.5 lb × 0.45359237 kg/lb = 1.13398 kg = 1,133.98 g

Result:40 oz (1,133.98 g)

Gym & Fitness: 20 Kilograms to Pounds

Translating barbell plate weights from metric gym equipment to pounds.

Calculation:20 kg / 0.45359237 kg/lb = 44.09245 lb

Result:44.09 lb (standard Olympic 20 kg plate)

Commercial Freight: 3 US Short Tons to Metric Tonnes

Converting heavy equipment hauling capacity for international shipping.

Calculation:3 tons × 2,000 lb = 6,000 lb; 6,000 lb × 0.45359237 kg = 2,721.554 kg = 2.7216 t

Result:2.7216 metric tonnes

Precision Limits & Official Standards

Uses exact NIST avoirdupois coefficients. Ounces in this tool represent weight/mass, not liquid volume.

Distinguishes avoirdupois mass ounces (28.35 g) from fluid ounces (volume).
Volume-to-mass conversions (e.g. cups of flour to grams) depend on ingredient density and will be covered in the dedicated Cooking Converter.