Pounds and grams
The avoirdupois pound is exactly 0.45359237 kilograms (1959 agreement) and contains 16 ounces. Body weight, food and product weights in the US, and body weight alongside stone in the UK, use pounds.
The gram is one thousandth of a kilogram. Recipes, nutrition labels, postage and small parcels use grams.
Worked example
Convert 1.5 lb: 1.5 × 453.59237 = 680.388555, so 1.5 pounds is 680.388555 grams. Likewise 2 lb = 907.18474 g.
Estimating in your head
Multiply by 450 for a quick figure; it is off by about 0.8%. For 1.5 lb that gives 675 g, against 680.389 exactly.
Going the other way
To convert grams to pounds, divide by 453.59237 (or multiply by 0.00220462262185). The swap button between the boxes opens that page.
How this works
g = lb × 453.59237
1 lb = 0.45359237 kg and 1 g = 0.001 kg, both by definition, so the factor is their ratio: 453.59237 exactly. Results drop binary floating-point noise beyond 15 significant digits and display at the precision you choose (6 significant figures by default). Copy result copies the full value.
Frequently asked
How many grams are in a pound?
1 pound = 453.59237 grams, exactly. The value follows from the unit definitions, so it never changes.
How do I convert pounds to grams?
Multiply by 453.59237. For example, 2 lb × 453.59237 = 907.18474 g.
What is 10 lb in grams?
10 lb = 4,535.9237 g. The table next to the converter lists more common values.
Is the result rounded?
Only on screen. The page computes with the exact definitions and removes floating-point noise past 15 significant digits; pick 3 to 12 significant figures, or use Copy result for the full value.
Sources
- NIST SP 811 Appendix B.8 — Factors for units listed alphabetically
- Federal Register 59-5442 (1959) — Refinement of values for the yard and the pound
- Wikipedia — Avoirdupois system
Reviewed Oct 17, 2026 · test vectors fixtures/units/mass/lbs-to-grams/