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Unit Converter
Weight, distance, volume, temperature.
How this tool works
Instant converter between metric, imperial and mixed systems. Useful for recipes (oz to grams), travel (mph to km/h), construction (feet to meters), and science (C/F/K). All offline, no telemetry.
Frequently asked questions
- Why does USA use imperial?
- Historical reasons. UK dropped imperial in 1965. USA adopted metric intent in 1975 but never executed. Liberia and Myanmar are the other 2 imperial countries; rest of world is metric.
- Inches to centimeters?
- 1 inch = 2.54 cm exactly. 1 foot = 30.48 cm. 1 yard = 91.44 cm.
- US vs UK gallons?
- 1 US gallon = 3.785 L. 1 UK (imperial) gallon = 4.546 L. 20% difference. This calculator uses US gallon by convention.
- Celsius to Fahrenheit formula?
- F = C × 9/5 + 32. Inverse: C = (F - 32) × 5/9. For Kelvin: K = C + 273.15.