Mass & Weight Converter: Kilograms, Grams, Pounds & Ounces
Convert mass and everyday weight measurements between Metric SI units (Kilograms, Grams, Milligrams, Metric Tons) and Imperial / US Customary avoirdupois units (Pounds, Ounces) using internationally standardized exact conversion constants.
Standard Mass Conversion Matrix (Base: Kilograms)
| Unit Name | Symbol | System | Equivalent in Kilograms (kg) |
|---|---|---|---|
| Kilogram | kg | Metric (SI Base) | 1.0 kg |
| Gram | g | Metric | 0.001 kg (1,000 g = 1 kg) |
| Milligram | mg | Metric | 0.000001 kg (1,000 mg = 1 g) |
| Metric Ton (Tonne) | t | Metric | 1,000 kg |
| Pound (Avoirdupois) | lb | Imperial / US Customary | 0.45359237 kg (exact) |
| Ounce (Avoirdupois) | oz | Imperial / US Customary | 0.028349523125 kg (28.3495 g) |
1. International Airline Baggage Limits
A checked suitcase allowance is 23 kilograms (kg). Find its maximum weight in pounds:
2. Precision Culinary & Coffee Scaling
A specialty coffee bag weighs 12 ounces (oz). Convert to grams for pour-over brewing ratios:
Mass Converter FAQs
What is the difference between mass and weight?
Mass measures the intrinsic amount of matter in an object (measured in kilograms or slugs) and remains constant everywhere in the universe. Weight is the gravitational force acting on that mass (measured in Newtons or pounds-force). In everyday commerce and cooking, “weight” is used colloquially to refer to mass.
How many ounces are in a pound, and how is it defined in grams?
Under the standard international avoirdupois system used for everyday goods, 1 pound equals exactly 16 ounces. Since the 1959 International Yard and Pound Agreement, 1 pound is defined as exactly 453.59237 grams, making 1 ounce equal to exactly 28.349523125 grams.