How to Convert Pounds to Kilograms

5 min read•June 1, 2025•Reviewed: June 1, 2026

✓Reviewed by Apex Conversion Editorial Team · Last reviewed June 1, 2026

To convert pounds to kilograms, multiply the pound value by 0.453592. Alternatively, divide by 2.20462 — both methods give the same result. The conversion is needed whenever US-measured weights need to be understood in metric terms: doctor's appointments abroad, international shipping, or following a fitness plan from a metric-using country.

For a mental shortcut: divide the pounds by 2 then subtract 10% of that result. For 150 lb: 75 − 7.5 = 67.5 kg (actual: 68.0 kg). Accurate to within 1%.

The Formula

kilograms = pounds × 0.453592
  — or —
kilograms = pounds ÷ 2.20462

Worked examples:
 100 lb × 0.453592 = 45.36 kg
 150 lb × 0.453592 = 68.04 kg
 180 lb × 0.453592 = 81.65 kg
 200 lb × 0.453592 = 90.72 kg

Mental shortcut (within 1%):
  Step 1: divide lb by 2
  Step 2: subtract 10% of that result
  Example: 180 lb → 90 − 9 = 81 kg  (actual: 81.65 kg)

Quick Reference Table

 lb      kg        lb      kg
────    ─────     ────    ─────
  10    4.54       130    58.97
  20    9.07       140    63.50
  30   13.61       150    68.04
  40   18.14       160    72.57
  50   22.68       170    77.11
  80   36.29       180    81.65
 100   45.36       190    86.18
 110   49.90       200    90.72
 120   54.43       250   113.40

Common Conversions by Context

Body weight: 150 lb = 68.0 kg, 170 lb = 77.1 kg, 200 lb = 90.7 kg. These are useful to know for medical forms when traveling to metric countries, where height is in cm and weight in kg.

Luggage: US airlines often enforce a 50 lb (22.7 kg) weight limit per checked bag; many international carriers use 23 kg (50.7 lb). Knowing this boundary prevents overweight fees. A bag packed to 48 lb is about 21.8 kg — safely under both limits.

Converting Pounds and Ounces Together

When you have a weight in pounds and ounces — for example, 12 lb 8 oz — first convert the ounces to a decimal fraction of a pound: 8 oz ÷ 16 = 0.5 lb. Then add: 12 + 0.5 = 12.5 lb. Now multiply: 12.5 × 0.453592 = 5.67 kg.

Alternatively, convert the whole weight to ounces first (12 lb × 16 + 8 oz = 200 oz), then multiply by 0.028349 kg/oz: 200 × 0.028349 = 5.67 kg. Both methods give the same result.

Quick Tips

✓
For body weight: 1 lb ≈ 0.454 kg. Losing 10 lb is losing about 4.5 kg.
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Gym plates: a standard 45 lb Olympic plate is 20.4 kg. A 35 lb plate is 15.9 kg.
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Food: a 1 lb cut of steak is about 454 g. A 5 lb bag of flour is about 2.27 kg.
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Shipping: many international parcel services charge per kg. Divide lb by 2.2 to estimate your parcel's metric weight.