Pounds to Grams Converter

Pounds to Grams

Convert pounds (lb) to grams (g). Both measure mass and weight, and the conversion comes up in cooking, shipping, fitness work.

The Formula

`` grams = pounds × 453.59237 pounds = grams × 0.00220462262185 `

One pound is 453.5924 grams, and one gram is 0.002205 pounds.

Conversion Table

Pounds	Grams
1 lb	453.5924 g
2 lb	907.1847 g
5 lb	2,267.96 g
10 lb	4,535.92 g
25 lb	11,339.81 g
50 lb	22,679.62 g
100 lb	45,359.24 g
500 lb	226,796.19 g
1,000 lb	453,592.37 g

The Other Direction

Grams	Pounds
1 g	0.002205 lb
2 g	0.004409 lb
5 g	0.011023 lb
10 g	0.022046 lb
25 g	0.055116 lb
50 g	0.110231 lb
100 g	0.220462 lb
500 g	1.1023 lb
1,000 g	2.2046 lb

What Each Unit Is

Pounds (lb) — exactly 0.45359237 kilograms, by the 1959 international agreement. The Roman libra — which is why its symbol is lb — refined through the English avoirdupois system.

Grams (g) — one thousandth of a kilogram. The metric unit for small masses; cooking, nutrition and postage all work in grams.

A Sense of Scale

• A bag of sugar is 2 lb
• A newborn is 6–9 lb
• US body weight is given in pounds
• A paperclip is about 1 g
• A sheet of A4 is 5 g
• A tennis ball is 58 g

Precision

The factor 453.59237 is rounded. For engineering work carry more digits than the table above, and round only at the end — rounding at each step compounds.

In Code

`javascript const poundToGram = (value) => value * 453.59237; ``

Where This Conversion Comes Up

• Cooking
• Shipping
• Fitness
• Medicine
• Manufacturing

How Many Decimals Do You Need?

Rounding the factor costs accuracy, and how much depends on the factor. Converting 137 lb with the factor truncated at each decimal place:

Decimals kept	Factor	137 lb becomes	Error
0	454	62,198	0.0899%
1	453.6	62,143.2	0.0017%
2	453.59	62,141.83	0.0005%
3	453.592	62,142.1	—
4	453.5924	62,142.16	—

A rule that holds for any conversion: round once, at the end. Rounding the factor and then multiplying compounds the error through every subsequent calculation, while carrying full precision and rounding the final answer does not.

The right number of significant figures is set by your input, not by the converter. If you measured pounds to three significant figures, the answer in grams is only good to three — writing more digits claims precision the measurement never had.