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Unit Converter

Convert between units across 8 categories: Length, Weight/Mass, Temperature, Area, Volume, Speed, Time, and Data storage. Swap button, show-all-units table, real-time conversion, and common quick-convert presets.

8 categories⇄ Swap button📋 All units table⚡ Real-time
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📖How to Use the Unit Converter

  1. 1
    Select a category

    Choose from 8 categories: Length, Weight/Mass, Temperature, Area, Volume, Speed, Time, or Data. Each category loads its unit list with the most commonly used units pre-selected.

  2. 2
    Enter a value and choose units

    Type the value to convert, then select the From and To units from the dropdowns. Click the ⇄ swap button to instantly reverse the conversion direction. The result updates in real time as you type.

  3. 3
    See the full unit table

    Toggle "Show all units" to display the input value converted into every unit in the category simultaneously — the complete conversion table. Quick-convert presets (like km to miles, kg to lbs, °C to °F) let you jump to common conversions instantly.

💡Quick Reference

Quick conversionResult
1 inch2.54 cm
1 mile1.609344 km
1 kg2.20462 lbs
0°C32°F / 273.15K
1 GB≈ 953.67 MiB

Frequently Asked Questions

How do I convert Celsius to Fahrenheit?

Select Temperature category, choose Celsius as the From unit and Fahrenheit as the To unit. The formula is °F = (°C × 9/5) + 32. Common reference points: 0°C = 32°F (freezing), 20°C = 68°F (room temperature), 37°C = 98.6°F (body temperature), 100°C = 212°F (boiling). For Kelvin: K = °C + 273.15. Kelvin is used in science and is the SI base unit for temperature.

How many centimetres are in an inch?

1 inch = 2.54 centimetres (exactly, by international definition since 1959). Therefore: 1 cm = 0.3937 inches. Common conversions: 1 foot = 30.48 cm, 1 yard = 91.44 cm, 1 mile = 1.609344 km (exactly). The inch-centimetre conversion is fundamental to all imperial-metric length conversions.

How do I convert kilograms to pounds?

1 kilogram = 2.20462 pounds (lbs). 1 pound = 0.453592 kg. Common conversions: 1 stone = 14 pounds = 6.35 kg (used for body weight in the UK), 1 metric ton = 1000 kg = 2204.62 lbs. Note that weight (force) and mass are often used interchangeably in everyday language, though they are technically different in physics.

What data storage units does this converter support?

The data category covers: bit, byte, kilobyte (KB), megabyte (MB), gigabyte (GB), terabyte (TB), petabyte (PB), and their binary equivalents (kibibyte KiB, mebibyte MiB, gibibyte GiB, tebibyte TiB). Note that 1 GB = 1,000,000,000 bytes (decimal, SI), while 1 GiB = 1,073,741,824 bytes (binary, used by operating systems). This distinction is why a "500 GB" hard drive shows as ~465 GiB in Windows.

What is the difference between weight and mass?

Mass is the amount of matter in an object, measured in kilograms (kg). It does not change regardless of location. Weight is the gravitational force acting on an object, measured in newtons (N). Weight = mass × gravitational acceleration (g ≈ 9.81 m/s² on Earth). On the Moon (g ≈ 1.62 m/s²), your weight is about 1/6 of your Earth weight but your mass is identical. In everyday language, "weight" in kilograms or pounds refers to mass.

What common conversions are covered by the quick presets?

Length: km↔miles, cm↔inches, m↔feet, m↔yards. Weight: kg↔lbs, g↔oz, kg↔stones. Temperature: °C↔°F, °C↔K. Area: m²↔ft², hectares↔acres. Volume: litres↔gallons, ml↔oz. Speed: km/h↔mph, m/s↔km/h. Time: hours↔minutes, days↔hours. Data: GB↔MB, TB↔GB. These cover the vast majority of everyday conversion needs across the metric and imperial systems.