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Pounds to Kilograms Converter

Convert a weight or mass from pounds to kilograms using the international avoirdupois pound. Results update instantly in your browser.

Instant resultAdjustable assumptionsNo data sent
Instant conversion

lb kg

Runs in your browser
kilograms0.453592kg

Result rounded to a maximum of six decimal places.

Conversion rulekg = lb × 0.45359237

1 lb = exactly 0.45359237 kg.

01
Method

How to convert pounds to kilograms

Multiply pounds by 0.45359237. The international pound is defined as exactly 0.45359237 kilograms.

Formulakg = lb × 0.45359237

1 lb = exactly 0.45359237 kg.

02
Worked example

Convert 150 lb to kg

Apply the conversion rule to 150 pounds. Using the default settings, the result is 68.038856 kg.

150 lb68.038856 kg
03
Quick reference

lb to kg conversion table

These pre-calculated values use the same formula and default settings as the converter above.

Common pounds to kilograms conversions
pounds (lb)kilograms (kg)
1 lb0.453592 kg
2 lb0.907185 kg
5 lb2.267962 kg
10 lb4.535924 kg
20 lb9.071847 kg
25 lb11.339809 kg
50 lb22.679619 kg
75 lb34.019428 kg
100 lb45.359237 kg
125 lb56.699046 kg
150 lb68.038856 kg
200 lb90.718474 kg
250 lb113.398093 kg
04
Practical use

Code and calculation snippets

Reuse the same conversion in a stylesheet or application. Keep contextual font sizes configurable when working with relative CSS units.

JavaScript
const kilograms = pounds * 0.45359237;
Python
kilograms = pounds * 0.45359237
05
Interpretation

Using the result accurately

Use more decimal places for technical work and round only the final result. For everyday measurements, two or three decimal places are usually easier to read.

Important limitation

This converter uses the international avoirdupois pound, which is the pound commonly used for body weight and goods. It does not convert troy pounds or force units.

Reference: NIST Guide to the SI: conversion factors.

Common questions

Pounds to Kilograms Converter FAQ

Short answers about the formula, assumptions, and displayed precision.

How do I convert pounds to kilograms?

Multiply pounds by 0.45359237. The international pound is defined as exactly 0.45359237 kilograms. For example, 150 lb converts to 68.038856 kg using the default settings.

What formula does this lb-to-kg converter use?

kg = lb × 0.45359237. 1 lb = exactly 0.45359237 kg.

What assumptions does the calculator make?

The converter uses the fixed relationship described in the formula: 1 lb = exactly 0.45359237 kg.

How many decimal places should I use?

The calculator shows up to six decimal places and removes unnecessary trailing zeros. Keep more precision for further calculations, then round the final value to suit your measurement or design system.