Conversions between kilograms and pounds are common in shopping, shipping, and fitness, while Celsius and Fahrenheit appear in travel, cooking, and weather. Although both are familiar, weight and temperature use different conversion methods.
Converting weight and mass
Manarty’s Unit Converter converts milligrams, grams, kilograms, tonnes, ounces, pounds, and stones. These conversions use fixed factors.
- 1 kilogram = 1,000 grams.
- 1 tonne = 1,000 kilograms.
- 1 pound = 0.45359237 kilograms.
- 1 ounce = 0.028349523125 kilograms.
Pounds to kilograms
Kilograms = pounds × 0.45359237
A weight of 150 pounds equals approximately 68.0389 kilograms.
Kilograms to pounds
Pounds = kilograms × 2.20462262
A weight of 70 kilograms equals approximately 154.324 pounds.
Weight is not volume
One litre cannot be assumed to equal one kilogram for every material. That approximation applies to water under particular conditions, while oils, flour, and metals have different densities.
Celsius to Fahrenheit
°F = (°C × 1.8) + 32
Thirty degrees Celsius equals (30 × 1.8) + 32 = 86°F.
Fahrenheit to Celsius
°C = (°F − 32) ÷ 1.8
Sixty-eight degrees Fahrenheit equals (68 − 32) ÷ 1.8 = 20°C.
Converting to Kelvin
K = °C + 273.15
Zero degrees Celsius equals 273.15 kelvin. Kelvin does not use a degree symbol; write 300 K.
Useful reference temperatures
- Water freezes: 0°C = 32°F.
- Water boils at standard pressure: 100°C = 212°F.
- 20°C = 68°F.
- 25°C = 77°F.
Choosing suitable precision
One decimal place may be enough for body weight or weather, while shipping and scientific work may require greater precision. Keep the full value during the calculation and round the final result.
Common mistakes
- Using 2.2 as an exact pound factor in a sensitive calculation.
- Forgetting to add 32 when converting to Fahrenheit.
- Confusing mass with volume.
- Using a degree symbol with kelvin.
- Rounding before the calculation is complete.
Frequently asked questions
How many pounds are in a kilogram?
One kilogram equals approximately 2.20462262 pounds.
When are Celsius and Fahrenheit equal?
The scales have the same numerical value at −40: −40°C = −40°F.
Can kelvin be negative?
The thermodynamic temperature scale has no value below absolute zero, which is 0 K.
Final takeaway
Weight conversions use fixed factors, while temperature conversions require formulas that account for different zero points. Choose the correct unit and precision, and do not confuse mass with volume.