Convert pounds (lbs) to kilograms (kg)
Enter a weight in pounds and click the button to instantly convert it to kilograms.
What this lbs to kg calculator does
This lbs to kg calculator helps you quickly convert pounds to kilograms using the exact conversion factor: 1 pound = 0.45359237 kilograms. It is useful for fitness tracking, nutrition planning, medical forms, travel documents, international shipping, and school assignments.
If you live in a country where pounds are common, but need to report your weight in metric units, this tool gives you an accurate answer in seconds.
How to convert lbs to kg (the formula)
To convert pounds to kilograms, multiply the number of pounds by 0.45359237.
Example:
- 150 lbs × 0.45359237 = 68.0388555 kg
- Rounded to two decimals: 68.04 kg
Common pounds to kilograms conversions
| Pounds (lbs) | Kilograms (kg) |
|---|---|
| 1 lb | 0.45 kg |
| 5 lbs | 2.27 kg |
| 10 lbs | 4.54 kg |
| 20 lbs | 9.07 kg |
| 50 lbs | 22.68 kg |
| 100 lbs | 45.36 kg |
| 150 lbs | 68.04 kg |
| 180 lbs | 81.65 kg |
| 200 lbs | 90.72 kg |
| 250 lbs | 113.40 kg |
Why this conversion matters
Pounds are part of the imperial system, while kilograms are part of the metric system. Many regions, industries, and institutions use kilograms as the standard unit for weight.
- Health and medical records: Most clinical systems store body weight in kg.
- Sports and fitness: International competitions often use metric units.
- Travel and shipping: Luggage and freight limits are usually listed in kilograms.
- Science and education: Metric units are standard in labs and textbooks.
Rounding tips for practical use
The exact conversion factor is long, but you usually do not need many decimals. Choose precision based on the situation:
- Everyday use: round to 1 decimal place.
- Fitness and nutrition: round to 1–2 decimal places.
- Medical or technical work: keep 2–3 decimal places or follow official guidance.
lbs vs kg: quick comparison
Pound (lb)
A pound is commonly used in the United States and a few other places for body weight, groceries, and package labeling.
Kilogram (kg)
A kilogram is the base metric unit of mass used globally. Because it is part of the SI system, kilograms are preferred in medicine, science, and international communication.
Frequently asked questions
Is 1 lb exactly 0.45 kg?
Not exactly. It is approximately 0.45 kg when rounded. The exact value is 0.45359237 kg.
How do I convert kg back to lbs?
Divide kilograms by 0.45359237, or multiply by 2.2046226218.
Can I use this for body weight and package weight?
Yes. The same conversion works for any weight measured in pounds.
Final thoughts
A reliable lbs to kg calculator saves time and reduces mistakes. Whether you are tracking fitness goals, updating forms, or preparing luggage, this converter gives you fast and accurate metric values. Bookmark this page so you can convert pounds to kilograms whenever you need.