kg to lbs Converter — Kilograms to Pounds (and Back)
This converter handles both directions of the most common weight conversion in everyday life: kilograms to pounds (kg → lb) and pounds to kilograms (lb → kg). One kilogram equals exactly 2.20462262185 pounds — a constant defined by the International Bureau of Weights and Measures (BIPM) since the 2019 SI redefinition. Use this tool whenever you need to convert body weight for medical records, shipping labels, fitness tracking, recipe scaling, or international product listings. The kilogram is the SI base unit of mass; the pound (avoirdupois) is the standard US customary and imperial unit. Knowing the precise factor — not the rounded 2.2 — matters when accuracy is critical, such as pediatric dosing or freight billing.
1 kilogram = 2.20462 pounds (lb). To convert kg to lbs, multiply by 2.20462. To convert lbs to kg, multiply by 0.453592. For example: 70 kg = 154.32 lb; 100 kg = 220.46 lb; 50 lb = 22.68 kg.
When to use this calculator
- Converting body weight from a foreign doctor's report (e.g., 72 kg → 158.7 lb) to enter into a US health insurance form
- Calculating the chargeable weight of an international parcel (e.g., 4.5 kg package → 9.92 lb) to estimate USPS or FedEx shipping costs
- Adapting a European recipe that lists ingredient weights in grams/kilograms (e.g., 1.2 kg flour → 2.65 lb) for a US kitchen scale
- Checking whether a suitcase meets an airline's 23 kg (≈50.7 lb) checked-bag weight limit before heading to the airport
- Converting a newborn's birth weight reported in pounds (7 lb 6 oz) to kilograms for a pediatric growth chart or vaccination dosing calculation
- Translating gym equipment plate weights (e.g., 20 kg bumper plates → 44.09 lb) when following a US-based powerlifting program
Worked Example: 70 kg to lbs
- Enter 70 in the Value field
- Select 'Kilograms → Pounds'
- Click Calculate → result: 154.3234 lb
How it works
3 min readHow to Convert kg to lbs (and lbs to kg)
The conversion between kilograms and pounds is based on a fixed, exact definition adopted in 1959 by the International Yard and Pound Agreement and reaffirmed by the 2019 SI revision:
/* Kilograms → Pounds */
pounds = kilograms × 2.20462262185
/* Pounds → Kilograms */
kilograms = pounds × 0.45359237
/* Full-precision constants (NIST) */
1 kg = 2.20462262185 lb (exact by definition)
1 lb = 0.45359237 kg (exact by definition)Most everyday calculations use the rounded factor 2.20462, which gives an error of less than 0.000001% for weights under 1,000 kg — negligible for any non-scientific application.
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kg to lbs Reference Table
| Kilograms (kg) | Pounds (lb) | Common Context |
|---|---|---|
| 1 kg | 2.205 lb | Standard weight reference |
| 5 kg | 11.023 lb | Small dumbbell / carry-on bag |
| 10 kg | 22.046 lb | Typical toddler weight |
| 20 kg | 44.092 lb | 20 kg barbell plates |
| 23 kg | 50.706 lb | Airline checked-bag limit (most carriers) |
| 32 kg | 70.548 lb | Max airline checked-bag limit |
| 50 kg | 110.231 lb | Average 12-year-old weight (CDC) |
| 60 kg | 132.277 lb | Lightweight boxing category |
| 70 kg | 154.324 lb | Average adult (global WHO estimate) |
| 80 kg | 176.370 lb | Average US adult male (approx.) |
| 90 kg | 198.416 lb | Typical heavyweight threshold |
| 100 kg | 220.462 lb | Approx. 15-stone benchmark |
| 150 kg | 330.693 lb | Bariatric threshold reference |
lbs to kg Reference Table
| Pounds (lb) | Kilograms (kg) | Common Context |
|---|---|---|
| 1 lb | 0.454 kg | Standard US weight unit |
| 5 lb | 2.268 kg | Bag of sugar / small dumbbell |
| 10 lb | 4.536 kg | Small dog / lightweight carry-on |
| 25 lb | 11.340 kg | Typical checked luggage |
| 50 lb | 22.680 kg | US airline weight limit (domestic) |
| 100 lb | 45.359 kg | Child / light adult reference |
| 150 lb | 68.039 kg | Average adult female (US CDC) |
| 200 lb | 90.718 kg | Average adult male (US CDC) |
| 250 lb | 113.398 kg | NFL linebacker average |
| 300 lb | 136.078 kg | Sumo wrestler lightweight |
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Typical Use Cases with Numbers
Example 1 — Body weight for a US health form:
A patient's file from a Canadian clinic reads 83.5 kg. To convert:83.5 × 2.20462 = 184.09 lb
The patient should enter 184 lb on the US insurance form.
Example 2 — Shipping a package internationally:
A seller ships a 6.8 kg box via USPS. The chargeable weight conversion:6.8 × 2.20462 = 14.99 lb ≈ 15 lb
Example 3 — Powerlifting total in competition:
An athlete lifts 545 kg combined (squat + bench + deadlift):545 × 2.20462 = 1,201.5 lb — "over 1,200 lb total"
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Common Mistakes
1. Using 2.2 instead of 2.20462 — Rounding to 2.2 introduces a 0.21% error. For a 100 kg person, that's a 0.462 lb difference — small for casual use, but meaningful for medical dosing or freight billing.
2. Forgetting to convert pounds + ounces separately — "7 lb 6 oz" is NOT 7.6 lb. There are 16 ounces in a pound, so 6 oz = 6/16 = 0.375 lb → total = 7.375 lb = 3.345 kg.
3. Confusing pounds-mass (lbm) with pounds-force (lbf) — This converter uses avoirdupois pounds (lbm), the standard for everyday weight.
4. Using the troy pound instead of avoirdupois — The troy pound (for precious metals) = 373.24 g vs. avoirdupois pound = 453.59 g. That's a ~21% error if mixed up.
5. Applying kg↔lb conversion to volume (liters) — Water weighs ~1 kg/liter, but most other liquids do not. Olive oil is ~0.916 kg/liter, not 1 kg/liter.
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Frequently asked questions
How many pounds is 1 kilogram?
1 kilogram = 2.20462 pounds (lb). The full-precision value is 2.20462262185 lb, as defined by the International Yard and Pound Agreement (1959) and maintained by NIST. For quick mental math, use 2.2 lb per kg (gives ~0.21% error).
How many kilograms is 1 pound?
1 pound = 0.453592 kilograms (exactly 0.45359237 kg by definition). To convert any weight in pounds to kg, multiply by 0.453592. For example: 150 lb × 0.453592 = 68.04 kg.
What is the kg to lbs formula?
The formula is: pounds = kilograms × 2.20462. For the reverse: kilograms = pounds ÷ 2.20462 (or × 0.453592). These factors are exact by international definition — not approximations. The longer form, 2.20462262185, is for scientific use.
How do I convert 70 kg to pounds?
70 kg × 2.20462 = 154.32 lb. This is one of the most searched conversions because 70 kg is close to the global average adult weight. In stones, that's 11 stone 0.3 lb (UK usage). In US practical terms: 154 lb on a scale.
How do I convert pounds and ounces to kilograms?
First convert ounces to a decimal fraction of a pound: divide the ounces by 16. Then add to the whole pounds. Example: 8 lb 12 oz = 8 + (12/16) = 8.75 lb. Then multiply by 0.453592: 8.75 × 0.453592 = 3.969 kg. Skipping the ounce conversion is the most common error with baby weights.
How does the kg to lbs conversion apply to airline baggage limits?
Most international airlines set checked-bag limits at 23 kg = 50.71 lb for economy class. The absolute max per bag is 32 kg = 70.55 lb (above which bags are refused regardless of fees). US domestic carriers (Delta, American, United) typically advertise 50 lb = 22.68 kg, slightly below the international 23 kg standard.
What is 100 kg in pounds?
100 kg = 220.46 lb (exactly 220.462262185 lb). This is a common benchmark — roughly 15 stone 10 lb in UK units. In fitness contexts, lifting or weighing 100 kg is a major milestone equivalent to 220 lb on US-calibrated equipment.
Is the pound used in the US the same as the UK pound?
Yes — both use the avoirdupois pound (453.59237 g), standardized since 1959. However, the UK also uses the 'stone' (14 lb = 6.35 kg) for body weight in everyday speech, which the US does not. There is also a troy pound (373.24 g) used only for precious metals — never use it for body or food weight.
How is this conversion used in medication dosing?
Many IV medications and pediatric drugs are dosed in mg/kg, but US patients' weights are often recorded in pounds. To convert: divide weight in lb by 2.20462 to get kg, then multiply by the dose in mg/kg. Example: a 132 lb patient receiving 5 mg/kg needs: 132 ÷ 2.20462 = 59.87 kg × 5 = 299.4 mg.