The Unit Converter converts between hundreds of units across length, weight, temperature, speed, area, volume, and data storage — with real-time conversion as you type and a quick-swap button to reverse the direction.

How to Use This Calculator

1. Select a Category from the dropdown (Length, Weight, Temperature, etc.).
2. Select the From and To units.
3. Enter a value — results update instantly as you type.
4. Use the ⇄ swap button to reverse the conversion direction.

Quick Reference: Common Conversions

• Length: 1 mile = 1.609 km | 1 foot = 30.48 cm | 1 inch = 2.54 cm
• Weight: 1 kg = 2.205 lbs | 1 stone = 6.35 kg | 1 oz = 28.35 g
• Temperature: °F = (°C × 9/5) + 32 | 0°C = 32°F | 100°C = 212°F
• Speed: 60 mph = 96.56 km/h | 1 knot = 1.852 km/h
• Volume: 1 gallon = 3.785 L | 1 cup = 240 mL | 1 fl oz = 29.57 mL
• Data: 1 GB = 1,024 MB | 1 TB = 1,024 GB

Temperature Is Different

Unlike most unit conversions (which are simple multiplication), temperature conversion requires both multiplication and addition because the Celsius and Fahrenheit scales have different zero points. Kelvin, the SI unit of temperature, starts at absolute zero (−273.15°C), making it the simplest for scientific calculations.

Frequently Asked Questions

Why are there two definitions of kilobyte?

In computing, 1 kilobyte can mean either 1,000 bytes (SI definition, used by storage manufacturers) or 1,024 bytes (binary definition, used by operating systems). This is why a “500 GB” hard drive shows as ~465 GB in your OS. This calculator uses the binary (1,024) definition.

What is a nautical mile?

A nautical mile equals 1 minute of arc of latitude (1/60th of a degree), making it directly tied to Earth’s geometry. It’s the standard unit for aviation and maritime navigation. 1 nautical mile = 1.852 km = 1.151 statute miles.