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Unit converters that
actually get it right.

Convert kg to lbs, Celsius to Fahrenheit, cm to inches — using exact SI-defined constants from the BIPM. Zero rounding errors. No ads. No signup.

  • Exact SI-defined constants — not rounded approximations
  • Live results on every keystroke — no button to press
  • Fully offline · no cookies · no data collected
Weightkg → lb
kg
Pounds
lb
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Formula: kg ÷ 0.45359237 = lbs — exact SI-defined constant

Temperature Converter

Celsius ↔ Fahrenheit · exact formula · reverse mode

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Popular conversions

How many pounds is one kilogram?

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One kilogram equals exactly 2.20462262184878 pounds — defined by the Bureau International des Poids et Mesures (BIPM) since the International Yard and Pound Agreement of 1959. The six values below cover the most-searched weight conversions.

Popular conversions

What is the formula for Celsius to Fahrenheit?

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The exact formula is °F = (°C × 9/5) + 32. Both the NIST (National Institute of Standards and Technology) and the International Bureau of Weights and Measures define this as algebraically exact — no rounding at any step. The six reference temperatures below cover cooking, weather, and body temperature.

How it works

Exact Conversion Factors

Every conversion uses the full BIPM-defined constant. 1 lb = exactly 0.45359237 kg. 1 inch = exactly 2.54 cm. Not approximations — internationally agreed legal definitions.

Live Results as You Type

No button to press. No page reload. Results update on every keystroke. The converter handles values from micro-weights to astronomical masses. Negatives and decimals both work.

No Tracking, No Accounts

All calculations run locally in your browser. No server calls during conversion. No cookies. No analytics on your inputs. Fully functional offline once the page loads.

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More in progress
WeightLive

kg, lb, g, oz

TemperatureLive

°C, °F, Kelvin

LengthSoon

cm, m, ft, in, mi, km

AreaSoon

m², ft², acres, ha

VolumeSoon

L, ml, fl oz, cups

SpeedSoon

km/h, mph, m/s, knots

TimeSoon

sec, min, hr, days

DataSoon

KB, MB, GB, TB, PB

PressureSoon

Pa, bar, psi, atm

EnergySoon

J, kWh, cal, BTU

Quick reference tables

Kilograms to Pounds — Complete Conversion Table

Exact factor: 1 kg = 2.20462262184878 lbs (BIPM). Values cover 1 kg to 150 kg.

Kilograms (kg)Pounds (lbs)
1 kg2.205 lbs
5 kg11.023 lbs
10 kg22.046 lbs
20 kg44.092 lbs
50 kg110.231 lbs
60 kg132.277 lbs
70 kg154.324 lbs
80 kg176.370 lbs
90 kg198.416 lbs
100 kg220.462 lbs
120 kg264.555 lbs
150 kg330.693 lbs

Formula: kg × 2.20462 = lbs · Reverse: lbs × 0.453592 = kg

Celsius to Fahrenheit — Full Reference Table

Formula: °F = (°C × 9/5) + 32. Reverse: °C = (°F − 32) × 5/9. From −40° to 250°C.

Celsius (°C)Fahrenheit (°F)
-40°C-40.0°F
0°C32.0°F
10°C50.0°F
20°C68.0°F
25°C77.0°F
37°C98.6°F
100°C212.0°F
180°C356.0°F
200°C392.0°F
220°C428.0°F
230°C446.0°F
250°C482.0°F

−40° is the only point where °C and °F are equal.

About unit conversion

Why do most unit converters give slightly wrong answers?

The International System of Units (SI) defines exact relationships between measurements. One pound equals exactly 0.45359237 kilograms — set by international agreement in 1959 and maintained by the Bureau International des Poids et Mesures (BIPM). One inch equals exactly 2.54 centimetres. These are legally binding definitions adopted by 51 signatory nations — not approximations.

Most converter sites round their constants. Using 2.205 instead of 2.20462 introduces a 0.003% error. Small for casual use, but meaningful for 1,000 kg shipments, pharmaceutical dosages, or engineering. The metric system governs science and trade across 190+ countries. US customary units and imperial units (including stone, troy ounce, and tonne) remain common in daily life. Since 2019, the kilogram is redefined by fixing the Planck constant to exactly 6.62607015 × 10⁻³⁴ J·s. Temperature is similarly exact: 0 Kelvin = −273.15°C (absolute zero).

Conversion reference

kg → lbs

kg × 2.20462

1 lb = 0.45359237 kg (BIPM)

lbs → kg

lbs × 0.453592

Avoirdupois pound definition

°C → °F

(°C × 9/5) + 32

Exact — no rounding

°F → °C

(°F − 32) × 5/9

Exact inverse

cm → in

cm ÷ 2.54

1 in = 2.54 cm (exact)

in → cm

in × 2.54

International inch

m → ft

m × 3.28084

1 ft = 0.3048 m (exact)

km → mi

km × 0.621371

1 mi = 1.609344 km (exact)

L → fl oz

L × 33.814

US fluid ounce (≈ 29.57 ml)

Common questions

How accurate are online unit converters?

How do you convert kilograms to pounds without a calculator?

Multiply the kg value by 2.205 for a quick estimate. For exact results, use 2.20462. Example: 70 kg × 2.20462 = 154.32 lbs. The pound is officially defined as 0.45359237 kg under the International Yard and Pound Agreement of 1959.

What is the exact formula for Celsius to Fahrenheit conversion?

The exact formula is °F = (°C × 9/5) + 32. To reverse: °C = (°F − 32) × 5/9. Both are algebraically exact with zero rounding. Water freezes at 0°C / 32°F and boils at 100°C / 212°F at standard atmospheric pressure.

How many pounds are in one kilogram exactly?

One kilogram equals exactly 2.20462262184878 pounds. This comes from the SI definition: 1 lb = 0.45359237 kg (exact), set by the Bureau International des Poids et Mesures (BIPM). Rounding to 2.205 introduces a 0.003% error — significant for medical doses or precision shipping.

Why do the United States and UK use different measurement units?

The US retained customary units (pounds, Fahrenheit, miles) after independence. Most of the world — including the UK for science and trade — switched to the International System of Units (SI), adopted internationally from 1960. The US is one of only three countries not officially metric, alongside Myanmar and Liberia.

What is normal human body temperature in Celsius and Fahrenheit?

Normal body temperature is 37°C (98.6°F) as established by Carl Reinhold August Wunderlich in the 19th century. Modern research places the normal adult range at 36.1°C–37.2°C (97°F–99°F). A fever is generally above 38°C (100.4°F).

How do I convert oven temperature from Celsius to Fahrenheit?

Apply °F = (°C × 9/5) + 32. Common oven conversions: 160°C = 320°F (low), 180°C = 356°F (moderate), 200°C = 392°F (hot), 220°C = 428°F (very hot). Fan-assisted ovens typically run 20°C hotter than stated, so reduce the temperature accordingly.

At what temperature are Celsius and Fahrenheit exactly equal?

The two scales meet at −40°. Both −40°C and −40°F represent the same temperature. You can derive this by setting (°C × 9/5) + 32 = °C and solving: 4C/5 = −32, so C = −40. It's the only crossover point in the entire scale.

Is there a quick mental math trick to estimate Celsius to Fahrenheit?

Double the Celsius value and add 30. Example: 25°C → (25 × 2) + 30 = 80°F (exact: 77°F). This approximation stays within 3°F between 10°C and 40°C, making it reliable for everyday estimates. For precision, use the exact formula: (°C × 9/5) + 32.