Mile

The long-distance unit of the US and UK roads.

Length

How it's defined

Defined as exactly 1,609.344 metres (5,280 feet). From the Roman "mille passus" — a thousand paces.

1 mi = 5,280 ft = 1,609.344 m — exact

Convert — honestly

mi equals

1609.344 m

Metre · factor exact — the base unit itself

63360 in

Inch · factor exact — exact by the 1959 yard-and-pound agreement

5280 ft

Foot · factor exact — exact by definition

Conversions run through the metre using the stated factors — no rounding beyond display precision, and every factor says whether it's exact or measured.

Where you meet it

Road signs and running apps in the US and UK
The "miles per gallon" on window stickers

Other ways to measure length

m Metre in Inch ft Foot

Source

This page is an authored summary of the authoritative definition — checkable one click away.

NIST Special Publication 811 — Guide for the Use of the SI