Unit Converter
Convert between units of length, weight, temperature, area, volume, speed, data, pressure, and energy.
Category
Convert
All Conversions
mm 1
cm 0.1
m 0.001
km 0.000001
in 0.03937008
ft 0.00328084
yd 0.001093613
mi 6.2137e-7
nmi 5.3996e-7
About
The Unit Converter supports nine measurement categories — Length, Weight/Mass, Temperature, Area, Volume, Speed, Data Size, Pressure, and Energy — covering every common unit in both the metric (SI) and imperial systems. Select a category, enter your value and source unit, and instantly see the result in any target unit. The "All conversions" table below the main converter shows every unit in the selected category at once, making it easy to compare values across systems. All conversions happen locally in your browser with no rounding until display.
How to use
- 1 Click a category tab (Length, Weight, Temperature, etc.) to select the measurement type.
- 2 Enter a value in the "From" field and select your source unit from the dropdown.
- 3 Select the target unit in the "To" field — the converted value updates instantly.
- 4 Click ⇄ to swap the from/to units.
- 5 Scroll to the "All conversions" table to see the value expressed in every available unit.
- How do I convert Celsius to Fahrenheit?
- Select the Temperature category, enter your °C value in the From field with °C selected, then choose °F in the To field. The formula is °F = °C × 9/5 + 32. For example, 100°C = 212°F (boiling point of water). The converter also supports Kelvin and Rankine.
- How do I convert km to miles?
- Select the Length category, enter your value with km selected as the source unit, then choose mi (miles) as the target. 1 km = 0.621371 miles. The converter supports all common length units: mm, cm, m, km, inches, feet, yards, miles, and nautical miles.
- What is the difference between MB and MiB?
- In the Data Size category, MB uses the SI definition (1 MB = 1,000,000 bytes = 10⁶ bytes), while MiB (mebibyte) uses the binary definition (1 MiB = 1,048,576 bytes = 2²⁰ bytes). Hard drive manufacturers typically use SI (decimal) prefixes, while operating systems often report in binary. The converter shows both.
- Are all conversions accurate?
- Yes — all conversion factors are based on exact SI definitions or widely accepted exact values (e.g., 1 inch = 25.4 mm exactly). Temperature conversions use exact formulas. The displayed values are rounded to 7 significant figures for readability; the underlying calculation uses JavaScript double-precision floating point.