Conversion Calculator
Convert between units of length, weight, temperature, volume, area, speed, time, data, energy, pressure, power and fuel economy.
How it works
Pick a category, enter a value and choose the units. Results update instantly, and the swap button reverses the direction.
Each category converts through one base unit using exact definitions, for example, 1 inch is exactly 25.4 mm and 1 pound is exactly 0.45359237 kg.
Temperature and fuel economy use formulas instead of simple factors. A table shows your value in every unit of the category.
Formula
result
Where:
- factor
- = Size of one unit in the category's base unit
- mpg
- = Miles per US gallon
Worked example
Convert 1 mile to kilometers, and 100 °F to Celsius.
1 mile = 1,609.344 m = 1.609344 km exactly. (100 − 32) × 5/9 = 37.7778 °C.
Maintaining Accuracy in Global Projects
In a globalized economy, the ability to convert between metric and imperial systems with high precision is essential. A key tip is to always use the exact conversion factors rather than rounded estimates. For example, 1 inch is defined as exactly 25.4 millimeters. While '2.5 centimeters' might be close enough for a quick guess, that small discrepancy can lead to catastrophic failures in precision engineering or manufacturing when tolerances are tight and components must fit perfectly.
Common Pitfalls in Daily Conversions
A frequent mistake is confusing U.S. Customary units with the British Imperial system. A U.S. gallon is significantly smaller than a U.K. gallon, which has led to numerous errors in the automotive and shipping industries. Another common pitfall occurs when converting digital storage units. Many people use 'megabytes' and 'mebibytes' interchangeably, but the 2.4% difference between decimal and binary bases adds up quickly at the terabyte level, often confusing consumers when checking hard drive capacities.
Culinary and Laboratory Accuracy
In the culinary arts, confusing weight with fluid volume is a classic error. While they share a name, they measure different properties; a fluid ounce of honey weighs much more than a fluid ounce of water. For baking, where precision is paramount, always convert to grams if possible, as weight is a more consistent measure of quantity than volume, which can be affected by how tightly a dry ingredient like flour or sugar is packed.
Frequently asked questions
A gigabyte (GB) is 1,000,000,000 bytes (decimal). A gibibyte (GiB) is 1,073,741,824 bytes (binary, 1024³). That's why a “500 GB” drive shows about 465 GiB on many computers.