Unit Converter

How This Calculator Works

A unit converter translates a measurement from one unit into an equivalent value in another unit — the same real-world quantity, expressed differently. Pick what you’re converting — length, weight, volume, temperature, area, speed, time, digital storage, pressure, energy, power, or angle — choose the unit you’re converting from and the unit you’re converting to, enter a value, and the result updates instantly. It covers the everyday conversions people look up most (centimeters to inches, kilograms to pounds, gallons to liters, Celsius to Fahrenheit) alongside less everyday but still common ones (acres to square feet, GB to MB, psi to bar, mph to km/h), all in one tool.

The Formula

Almost every dimension here works the same way: every unit within a dimension has a fixed ratio to one “canonical” unit (meters for length, kilograms for weight, pascals for pressure, and so on). Converting from one unit to another is just:

$$\text{Result} = \frac{\vA{\text{Value}} \times \vB{\text{Ratio of "From" Unit}}}{\vC{\text{Ratio of "To" Unit}}}$$

Temperature is the one real exception — Celsius, Fahrenheit, and Kelvin don’t share a common zero point, so converting between them needs an offset, not just a ratio:

• Celsius to Fahrenheit: $(\text{celsius} \times 9 \div 5) + 32$
• Fahrenheit to Celsius: $(\text{fahrenheit} - 32) \times 5 \div 9$
• Celsius to Kelvin: $\text{celsius} + 273.15$

Digital storage uses binary (1024-based) prefixes, the conventional assumption for a “data storage converter” — 1 KB is 1,024 bytes here, not 1,000, matching how operating systems typically label file and drive sizes.

Worked Example

Converting 1 mile to kilometers:

A mile is defined as exactly 1,609.344 meters, and a kilometer is 1,000 meters, so:

$$\vA{1} \text{ mile} \times \vB{1{,}609.344} \text{ (meters per mile)} \div \vC{1{,}000} \text{ (meters per km)} = 1.609344 \text{ km}$$

For temperature, converting 0°C to Fahrenheit: $(0 \times 9 \div 5) + 32 = 32°F$ — the freezing point of water in both scales, which is a useful way to sanity-check that a temperature conversion tool is working correctly. And for digital storage, converting 1 GB to megabytes: $1 \times 1{,}024 = 1{,}024 \text{ MB}$, since a gigabyte is 1,024 megabytes under the binary convention this calculator uses.