Weight Conversion

Pounds to Kilograms: Complete Conversion Guide

5 min read · Updated May 2025

Whether you're tracking your weight, calculating shipping costs, or following a recipe from another country, converting pounds to kilograms is one of the most common unit conversions in daily life. This guide gives you the formula, a complete reference chart, and everything you need to convert quickly and accurately.

Quick answer: 1 pound = 0.453592 kilograms. To convert pounds to kg, multiply by 0.4536. To convert kg to pounds, multiply by 2.2046.

The Formula

The exact conversion factor between pounds and kilograms is defined by international agreement:

kg = lb × 0.453592
lb = kg × 2.204623

For quick mental maths, you can use the approximation of dividing by 2.2 to go from pounds to kg, or multiplying by 2.2 to go from kg to pounds.

Pounds to Kilograms Conversion Chart

Pounds (lb)Kilograms (kg)Common Use
1 lb0.45 kgButter, small package
5 lb2.27 kgBag of flour
10 lb4.54 kgDumbbells, carry-on limit
20 lb9.07 kgChecked baggage
50 lb22.68 kgShipping freight
100 lb45.36 kgWeight milestone
150 lb68.04 kgAverage person weight
200 lb90.72 kgHeavy person weight

Why Do We Have Two Systems?

The pound is part of the Imperial system, primarily used in the United States, while the kilogram is part of the International System of Units (SI), used by most of the world. The kilogram is formally defined as exactly 1,000 grams and is the base unit of mass in the metric system.

The pound traces its roots to ancient Roman units of measurement and has been used in England and its territories for centuries. The US retained it after independence, making it one of only three countries in the world — along with Liberia and Myanmar — that hasn't officially adopted the metric system as its primary measurement standard.

Common Conversions at a Glance

Kilograms (kg)Pounds (lb)
1 kg2.205 lb
5 kg11.023 lb
10 kg22.046 lb
50 kg110.231 lb
75 kg165.347 lb
100 kg220.462 lb

Convert Pounds to Kilograms Instantly

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