Lbs to KG Converter
Exact both ways — bodyweight, plates, and luggage without the 2.2 shortcut.
Type in either field — the other updates instantly.
Lbs to KG chart
| Pounds | Kilograms |
|---|---|
| 1 lb | 0.45 kg |
| 2 lb | 0.91 kg |
| 5 lb | 2.27 kg |
| 10 lb | 4.54 kg |
| 20 lb | 9.07 kg |
| 25 lb | 11.34 kg |
| 45 lb | 20.41 kg |
| 50 lb | 22.68 kg |
| 100 lb | 45.36 kg |
| 110 lb | 49.9 kg |
| 120 lb | 54.43 kg |
| 135 lb | 61.23 kg |
| 150 lb | 68.04 kg |
| 165 lb | 74.84 kg |
| 180 lb | 81.65 kg |
| 200 lb | 90.72 kg |
| 220 lb | 99.79 kg |
| 250 lb | 113.4 kg |
| 300 lb | 136.08 kg |
| 500 lb | 226.8 kg |
How this is calculated
kg = lb × 0.45359237 (exact — the pound is defined in kilograms)
Going from pounds into metric is the traveler-and-lifter direction: a 50 lb checked-bag limit is 22.68 kg, a 45 lb Olympic plate is 20.41 kg, and a 180 lb bodyweight is 81.65 kg. The popular ÷2.2 shortcut runs about 0.2% hot — harmless for chat, wrong for dosing or shipping paperwork.
Since 1959 the avoirdupois pound has been defined as exactly 0.45359237 kg. This page uses that full definition, so the only rounding is the display precision you read.
Pounds to kilograms is the everyday direction for anyone using American recipes, US gym equipment, or medical guidance written for an imperial audience. Drug dosing in particular is calculated per kilogram almost everywhere, so a weight known in pounds has to be converted before any dose is worked out — and the error runs one way, since halving is a common shortcut and produces a figure roughly 10% too high.
One pound is exactly 0.45359237 kg, and the rough rule of dividing by 2.2 is accurate to about 0.2%. For anything clinical or commercial, use the exact factor: on a 90 kg patient the difference between the shortcut and the true value is enough to matter for a weight-based dose.
Frequently asked questions
How many kg is 1 lb?
Exactly 0.45359237 kg. Quick mental check: halve the pounds and knock off ~2% — 180 lb → 90 − 8.35 ≈ 81.6 kg.
Why does my gym use both?
Barbell plates come in both traditions: a "45" plate is 45 lb (20.41 kg) in US gyms, while Olympic competition plates are true 20 kg (44.09 lb). Same bar, two labeling worlds — this page translates between them exactly.
What is 50 lbs in kg (the luggage question)?
22.68 kg. Most airlines cap checked bags at 50 lb / 23 kg — the 23 is that same limit rounded up, which is why a 22.9 kg bag can read as overweight on a pound scale.
Is ÷2.2 accurate enough?
It carries a 0.2% error (the true factor is 2.20462 lb per kg). Fine for conversation; use the exact factor for medication math, shipping declarations, or anything with a hard threshold.