Accurate, standards-based conversions
All conversion factors use internationally defined constants (SI units). Length, weight, area, volume, speed and data are simple ratios; temperature uses exact formulas because the scales have different zero points.
| Handy everyday conversions | Value |
|---|---|
| 1 inch | 2.54 cm (exact) |
| 1 foot | 30.48 cm |
| 1 kg | 2.20462 lb |
| 1 mile | 1.60934 km |
| 1 litre | 0.264172 US gallon |
| 1 acre | 4046.86 m² |
FAQs
Why does temperature use a formula, not a ratio?
Because Celsius, Fahrenheit and Kelvin have different zero points. °F = °C × 9/5 + 32, and K = °C + 273.15. A simple multiplier can't handle the offset.
Are these the same units used officially in India?
Yes — India uses the metric (SI) system officially. Imperial units (feet, pounds, gallons) are included for convenience when dealing with older documents or US sources.