Common measurement conversions
Use the value and its unit together. Values labelled rounded are display shortcuts; use the converter for an input that is not listed.
| Starting value | Converted value | Precision note |
|---|---|---|
| 1 cm | 0.393701 in | Rounded |
| 1 in | 2.54 cm | Exact |
| 1 m | 3.28084 ft | Rounded |
| 1 ft | 0.3048 m | Exact |
| 1 km | 0.621371 mi | Rounded |
| 1 mi | 1.609344 km | Exact |
| 1 kg | 2.20462 lb | Rounded |
| 1 lb | 0.45359237 kg | Exact |
| 1 L | 0.264172 US gal / 0.219969 imp gal | Rounded; gallon types differ |
| 1 sq m | 10.7639 sq ft | Rounded |
| Celsius to Fahrenheit | °F = (°C × 9/5) + 32 | Formula |
| Fahrenheit to Celsius | °C = (°F - 32) × 5/9 | Formula |
Speed: kilometres per hour to miles per hour
mph = km/h ÷ 1.609344. The reverse is km/h = mph × 1.609344. Displayed speeds below are rounded to two decimals.
| Kilometres per hour | Miles per hour |
|---|---|
| 10 km/h | 6.21 mph |
| 30 km/h | 18.64 mph |
| 50 km/h | 31.07 mph |
| 60 km/h | 37.28 mph |
| 80 km/h | 49.71 mph |
| 100 km/h | 62.14 mph |
| 110 km/h | 68.35 mph |
Food energy: kilojoules and calories
Food-label Calories mean kilocalories (kcal). These examples use 1 kcal = 4.184 kJ, the thermochemical convention used by our energy converters. Divide kJ by 4.184 to get kcal; multiply kcal by 4.184 to get kJ.
| Starting energy | Converted energy |
|---|---|
| 100 kJ | 23.90 kcal |
| 250 kJ | 59.75 kcal |
| 500 kJ | 119.50 kcal |
| 1000 kJ | 239.01 kcal |
| 2000 kJ | 478.01 kcal |
| 100 kcal | 418.4 kJ |
| 250 kcal | 1,046.0 kJ |
| 500 kcal | 2,092.0 kJ |
Download the PDF
Print the reference tables or save them beside your calculator results.
Download Metric to Imperial Conversion Chart PDFChoosing the correct unit
A US gallon and an imperial gallon hold different volumes. An ounce of mass is also different from a fluid ounce of volume. This chart uses ordinary international length units and the avoirdupois pound; it does not use the retired US survey foot or precious-metal troy ounces.
Round once, after converting. For example, 100 km/h ÷ 1.609344 = 62.1371... mph, displayed here as 62.14 mph.
Related tools and guides
Frequently asked questions
Are all the chart values exact?
No. Entries labelled exact are definitions; the other numerical conversions are rounded. The pound is exactly 0.45359237 kg, not exactly 0.453592 kg.
Does this PDF include speed and food energy?
Yes. It contains both a km/h-to-mph reference table and kJ-to-kcal examples, with the reverse formulas.
Can I print the tables?
Yes. The PDF has a measurements and speed page and a separate food-energy reference page.
Sources and method
- NIST Guide to the SI, Appendix B.8 - Conversion factors for length, volume, area, speed and thermochemical calories.
- NIST Guide to the SI, footnotes 9 and 22 - Exact thermochemical calorie and international pound definitions.