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Unit Conversion Calculator

Convert between metric and imperial units for length, mass, volume, speed, pressure, and more. Comprehensive reference for everyday calculations.

Unit Conversion illustration

About This Tool

Comprehensive Unit Converter

The Unit Conversion Calculator is your all-in-one tool for converting between metric (SI) and imperial units across multiple categories. Whether you need to convert lengths, masses, volumes, speeds, pressures, or areas, this comprehensive calculator handles them all with precision.

In our globalized world, being able to convert between different unit systems is essential. Scientists use SI units, while the United States commonly uses imperial units. This tool bridges that gap, making it invaluable for international collaboration, travel, cooking, engineering, and everyday calculations.

Length: meters, feet, inches, miles, kilometers, yards
Mass: kilograms, pounds, ounces, grams, tonnes
Volume: liters, gallons, cups, milliliters, fluid ounces
Speed, Pressure, and Area conversions included

Unit Converter

Select a category and convert

About Unit Conversion

Unit conversion is the process of changing a value from one unit to another within the same measurement category.

The two main measurement systems are:

  • SI (Metric) - Used worldwide in science. Based on powers of 10.
  • Imperial/US - Used in the US, UK (partially). Historical origins.
Result = Value × (From ÷ To)

General conversion formula

Common Length Conversions

  • 1 inch = 2.54 cm
  • 1 foot = 30.48 cm
  • 1 yard = 0.9144 m
  • 1 mile = 1.609 km

Common Mass Conversions

  • 1 ounce = 28.35 g
  • 1 pound = 453.6 g
  • 1 kg = 2.205 lb
  • 1 stone = 6.35 kg

Note

Some units have regional variations (e.g., US gallon vs UK gallon). This converter uses US customary units for imperial measurements.