Unit Converter

Length, mass, temperature, area, volume, speed, time and data.

Value

From

1 km in mile

0.621371 mi

1 km = 0.621371 mi

How it works

Every group except temperature converts through a base unit — metres, kilograms, seconds and so on — so a conversion is a single multiplication and the result updates as you type. Temperature is different: Celsius, Fahrenheit and Kelvin have different zero points, so they're converted through Celsius rather than scaled.

Example

1 km = 1,000 m
0 °C = 32 °F
1 kg ≈ 2.2046 lb

Common mistakes

Treating KB and KiB as the same size. 1 KB is 1,000 bytes but 1 KiB is 1,024 — a small gap per unit that adds up to nearly 5% by the time you reach GB vs. GiB. Match the unit to what actually labelled your number. For network speed, a related mix-up is Mbps (megabits) vs. MB/s (megabytes) — the Download Time Calculator converts between the two.

Data sizes use both decimal units (1 KB = 1,000 bytes) and binary units (1 KiB = 1,024 bytes), since operating systems and drive manufacturers disagree about which is which.

About this calculator

One converter for the eight unit families you actually meet: length, mass, temperature, area, volume, speed, time and digital storage. Pick a category, choose the from and to units, and the result updates as you type — the swap button flips the direction instantly.

Conversions run through exact standard factors (a mile is defined as 1.609344 km, a pound as 0.45359237 kg), so round-tripping a value returns what you started with.

Frequently asked questions

Why is temperature conversion different from the others?

Most units differ by a pure scale factor, but Celsius and Fahrenheit also have offset zero points, so °F = °C × 9⁄5 + 32 rather than a simple multiplication. The converter applies the full formula — 0 °C is 32 °F, and −40° is the one point where both scales agree.

How many kilometres is a mile?

Exactly 1.609344 km, by international definition. Going the other way, 1 km is about 0.6214 miles — a 10 km run is roughly 6.2 miles.

Is a kilobyte 1000 bytes or 1024?

Both conventions exist, and the converter offers both: KB, MB, GB and TB use powers of 1000, while KiB, MiB, GiB and TiB use powers of 1024. Storage vendors use decimal units, which is why a '1 TB' drive shows up as roughly 931 GiB in your operating system.

Tile CalculatorWork out how many floor tiles and boxes to buy, with a waste allowance, rounded up.

Concrete CalculatorFind the volume of concrete for a slab, footing or column in m³, ft³ and yd³, with bags if you want them.

Paint CalculatorEstimate litres or gallons of paint for a room from wall sizes, openings, coats and coverage.

Download Time CalculatorHow long a file takes to download at a given connection speed.

Scientific CalculatorTrigonometry, logarithms, powers and roots in one expression.