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Pounds to grams

Multiply pounds by 453.5924 to get grams.

1 lb = 453.5924 gNIST HB 44 · BIPM SI
lb
1,360.7771g

3 lb = 1,360.7771 g

How to convert pounds to grams

The gram is one thousandth of a kilogram (10⁻³ kg) in the SI. The pound is exactly 0.45359237 kilograms — the international avoirdupois pound fixed by the 1959 agreement of the US, UK and Commonwealth.

Worked example — 3 lb: 3 × 453.5924 = 1,360.7771 g.

Pounds to grams table

Common conversions. The reverse table is on grams to pounds.
PoundsGrams
0.25 lb113.3981 g
0.5 lb226.7962 g
1 lb453.5924 g
2 lb907.1847 g
3 lb1,360.7771 g
5 lb2,267.9619 g
10 lb4,535.9237 g
20 lb9,071.8474 g
50 lb22,679.6185 g

Reverse and related

About pounds and grams

Pound (lb)

1 lb = 453.5924 g

Definition. Exactly 0.45359237 kilograms — the international avoirdupois pound fixed by the 1959 agreement of the US, UK and Commonwealth

History and origin

The pound descends from the Roman libra, whose name still gives the symbol lb. Many regional pounds circulated for centuries before the 16-ounce avoirdupois pound became the English-speaking standard for trade. In 1959 the United States, the United Kingdom and other Commonwealth countries signed the international yard and pound agreement, fixing the pound at exactly 0.45359237 kilograms.

Current use

The pound is the everyday unit of weight in the United States, and informally in the United Kingdom, for body weight, food packaging and shipping, while most of the world states the same weights in kilograms.

Source: NIST Handbook 44, Appendix C §5 (Tables of Equivalents)

Gram (g)

1 g = 0.00220462 lb

Definition. One thousandth of a kilogram (10⁻³ kg) in the SI

History and origin

The gram was the original base of the metric system set out in 1795, defined as the mass of one cubic centimetre of water at the melting point of ice, before the larger kilogram was chosen as the SI base unit. It is now simply one thousandth of a kilogram.

Current use

Grams are the everyday metric unit for small masses: recipe ingredients, nutrition labels, medicine doses and postage.

Source: BIPM, The International System of Units (SI), 9th ed. (2019)

Where people use this

Pounds: body weight in the US, gym plates, shipping weights. Grams: recipe and food weights, nutrition labels, postage. 1 pound is about 453.6 g.

How we know this is right
The factor is fixed by the standards that define the units, not chosen — so it is exact, not a measurement:
1 g = 0.002204622622 lb, so 1 lb = 1 ÷ 0.002204622622 = 453.5924 g.

Every value is carried to full double precision; the display is rounded.

Sources: BIPM, The International System of Units (SI), 9th ed. (2019); NIST Handbook 44, Appendix C §5 (Tables of Equivalents).

Questions people ask

How many grams is 1 pound?

One pound is about 453.6 grams (exactly 453.59237 g). To convert pounds to grams, multiply by 453.6.

How many grams is 2 lb?

2 pounds is about 907.2 grams.

Why is a pound 453.6 grams?

The pound was fixed at exactly 0.45359237 kg by the 1959 international agreement, which is 453.59237 grams.

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