Pounds to Kilograms Converter

1 pound = 0.45359237 kg · 1 kg = 2.20462 lb

Weight & Mass

How to Use This Tool

Pounds to kilograms converter

Multiply pounds by 0.45359237 to get kilograms. That factor is exact, defined by international agreement since 1959. One pound is 0.453592 kg, and one kilogram is 2.20462 lb. The converter on this page uses that precise value for every calculation.

Pounds to kilograms quick reference

Pounds (lb) Kilograms (kg)
1 lb 0.454 kg
2 lb 0.907 kg
5 lb 2.268 kg
10 lb 4.536 kg
15 lb 6.804 kg
20 lb 9.072 kg
25 lb 11.340 kg
30 lb 13.608 kg
40 lb 18.144 kg
50 lb 22.680 kg
75 lb 34.019 kg
100 lb 45.359 kg
120 lb 54.431 kg
140 lb 63.503 kg
150 lb 68.039 kg
160 lb 72.575 kg
170 lb 77.111 kg
180 lb 81.647 kg
200 lb 90.718 kg
250 lb 113.398 kg
300 lb 136.078 kg

For values not listed, type them into the converter above or multiply by 0.453592.

How to convert pounds to kilograms

The formula

kilograms = pounds x 0.45359237

For a rough estimate, divide by 2.2. That gets you within 0.3% of the exact answer, which is close enough for most everyday situations.

Example 1: body weight

A person weighs 165 lb. 165 x 0.453592 = 74.84 kg. Most scales round to one decimal, so 74.8 kg.

Example 2: luggage

An airline has a 23 kg checked bag limit. You packed 48 lb. 48 x 0.453592 = 21.77 kg. You are under the limit by about 1.2 kg.

Example 3: pet weight

A dog weighs 62 lb at the vet. 62 x 0.453592 = 28.12 kg. Drug dosages for animals are calculated per kilogram, so this conversion matters for medication.

Example 4: dumbbell weight

A set of 35 lb dumbbells. 35 x 0.453592 = 15.88 kg. The nearest standard metric dumbbell is 16 kg, so they are nearly identical.

When you need this conversion

Medical and health

Most of the world records body weight in kilograms. US medical charts use pounds, but drug dosing, BMI calculations, and international medical literature work in kg. A 180 lb patient is 81.6 kg. Getting this wrong affects medication dosages, anesthesia calculations, and nutritional assessments.

Travel and shipping

Airlines outside the US post baggage limits in kilograms. A typical economy limit is 23 kg (about 50.7 lb). Overweight fees kick in at the kilogram threshold, not a rounded pound figure, so knowing the exact conversion avoids surprises at check-in.

Fitness

Olympic weightlifting uses kilogram plates. A 225 lb bench press is 102.1 kg. Gym equipment varies by country, and converting between the two systems is part of following any international training program.

Cooking in bulk

Restaurant supply and wholesale food comes in pound quantities in the US. European recipes for large batches specify kilograms. A 10 lb bag of flour is 4.54 kg. Scaling recipes across systems without converting accurately throws off ratios.

Common objects in pounds and kilograms

Object Pounds Kilograms
Smartphone 0.4 lb 0.18 kg
Bag of sugar (small) 5 lb 2.27 kg
House cat 8-11 lb 3.6-5.0 kg
Bowling ball (regulation) 6-16 lb 2.7-7.3 kg
Car tire 20-25 lb 9.1-11.3 kg
Medium suitcase (packed) 40-50 lb 18.1-22.7 kg
Large dog (Labrador) 55-80 lb 24.9-36.3 kg
Bag of concrete 60-80 lb 27.2-36.3 kg

Tips for accurate conversions

  • The quick mental shortcut is to divide pounds by 2.2. For 150 lb: 150 / 2.2 = 68.2 kg. The precise answer is 68.04 kg, so the shortcut overshoots by about 0.2%.
  • For body weight, one decimal place is enough. Medical records rarely go beyond that, and bathroom scales are not accurate to the gram anyway.
  • Pounds and kilograms both measure mass in everyday use. The technical distinction between mass and weight only matters in physics and engineering contexts.
  • If you are converting stones to kilograms, first multiply stones by 14 to get pounds, then multiply by 0.453592. Or multiply stones directly by 6.35029.

Frequently asked questions

How many kilograms is 1 pound?

1 lb = 0.453592 kg. The exact value is 0.45359237 kg.

How many pounds is 1 kilogram?

1 kg = 2.20462 lb.

How do I convert 150 pounds to kg?

150 x 0.453592 = 68.04 kg.

What is 200 pounds in kilograms?

200 x 0.453592 = 90.72 kg.

Is 1 kg equal to 2 pounds?

No. 1 kg equals 2.205 pounds, not 2. The difference is about 10%, which adds up quickly at higher weights.

How do I convert kg back to pounds?

Multiply kilograms by 2.20462. For example, 70 kg x 2.20462 = 154.32 lb.

Why do some countries use pounds and others use kilograms?

The US, Liberia, and Myanmar still use the imperial system for everyday measurements. Most other countries adopted the metric system, which uses kilograms. The UK uses a mix, with stones and pounds for body weight and kilograms for most other purposes.

What is the difference between a pound and a troy pound?

A standard (avoirdupois) pound is 453.592 grams. A troy pound, used for precious metals, is 373.242 grams. Troy pounds have 12 ounces instead of 16, and each troy ounce is 31.1 grams instead of 28.35 grams.

Measurement guides

Formula & Explanation

The pound is defined as exactly 0.45359237 kilograms by international agreement. The reverse factor (1 kg = 2.20462 lb) is a rounded representation of 1/0.45359237.

Frequently Asked Questions

How do I convert pounds to kilograms?

To convert pounds to kilograms, multiply the pounds value by 0.45359237. For example, 1 pounds = 0.45359237 kilograms. Our converter above does this calculation instantly as you type.

What is the formula for pounds to kilograms?

The formula is: kilograms = pounds u00d7 0.45359237. This is a linear conversion, meaning the ratio is constant regardless of the value being converted.

Is this pounds to kilograms converter accurate?

Yes. Our converter uses the internationally recognized conversion factor of 1 pounds = 0.45359237 kilograms, which is the standard accepted by NIST and most engineering references. Results are rounded to a sensible precision to avoid floating-point noise.

Can I convert kilograms back to pounds?

Yes. The converter is bidirectional u2014 type in either field and the other updates automatically. To convert kilograms to pounds, divide the kilograms value by 0.45359237, or simply use the swap button (u21c4) between the two fields.

Why would I need to convert pounds to kilograms?

Common reasons include international travel (different countries use different measurement systems), cooking recipes from other regions, engineering and construction work, scientific calculations, and understanding product specifications listed in unfamiliar units.