Most of the countries in the world now use the metric system or international system (SI). The old British imperial system of weights and measures survives, in various forms, the United States, to UK, to Canada and at Liberia to varying degrees. For example, in the United States, you will find the metric system used only in scientific or military contexts, while in the United Kingdom and Canada, the use of the metric system is more common. Scientific language exclusively uses the metric system in all countries of the world.
To get by in countries that use a different system than the one you're used to, it helps to know a few equivalents. We use the "=" sign below, but some are approximations.
Temperature
← gel | cold | costs | way | lukewarm | hot | stifling | cooked → | |||||||||||
° C | -40 | -18 | -4 | 0 | 4 | 7 | 10 | 13 | 15 | 18 | 21 | 24 | 26 | 30 | 32 | 35 | 40 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
° F | -40 | 0 | 25 | 32 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 | 104 |
{{unit | 100 | ° C}} = {{unit | 212 | ° F}} = Water boils {{unit | 58 | ° C}} = {{unit | 136 | ° F}} = Higher temperature recorded on Earth {{unit | 37 | ° C}} = {{unit | 98.6 | ° F}} = Temperature of the human body {{unit | 20 | ° C}} = {{unit | 68 | ° F} } = Room temperature {{unit | 0 | ° C}} = {{unit | 32 | ° F}} = Water freezes {{unit | -18 | ° C}} = {{unit | 0 | ° F}} = {{unit | -40 | ° C}} = {{unit | -40 | ° F}} = - 40 °! {{unit | -89 | ° C}} = {{unit | -129 | ° F}} = Lowest temperature recorded on earth {{unit | -273 | ° C}} = {{unit | -459 | ° F}} = Absolute zero
To convert degrees Celsius to degrees Fahrenheit, double the number of degrees and add 30. To convert degrees Fahrenheit to Celsius, subtract 30 and divide by two. This gives a good approximation. For scientific uses:
Length
- 1 inch (inch) (1") = 2,54 cm
- 1 foot (football) (1') = 30 cm
- 1 thousand (mile) = 1,6 km
Weight
- 1 kg = 2.2 pounds
- 1 fluid ounce (ounce) = 28.54 grams
- 1 book (pound) = 454 grams
Volume
In the US and UK, four quarts = 1 gallon and 2 quarts = 1 quart. However, American units are smaller than their British counterparts. One American quart is 32 fluid ounces while the British one is 40, one liter is about 35 fluid ounces. A US gallon is 128 ounces, or 3.78 liters, while an imperial gallon is 160 ounces, or 4.54 liters.
For car and motorcycle engines, the capacity can be given in cc or liters and cubic inches. 1000 cc or a liter is 61 cubic inches.