KM to Miles Converter
Convert kilometres to miles and miles back to kilometres.
Formula and sources updated · Data sources · 1View algorithm, constants and default inputs (JSON)
1 mi = 1.609344 km
About this calculator
A mile is 1.609344 kilometres exactly. The rough mental shortcut of multiplying by 0.6 gets you close, but this converter gives the precise figure.
Worked example
calculated with the default values below
Value 10 · Direction ⇄ · Decimal places 4 · From Kilometres (km) · To Miles (mi) Result 6.2137 · In metres 10,000 m · In nautical miles 5.3996 nmi
Method and assumptions
1 international mile = 1.609344 km; 1 nautical mile = 1.852 km. Only the displayed unit definitions are converted; rounding and measurement uncertainty are separate.
Data sources
Disclaimer
These calculators give general conversion results. Rounding and the precision of the value you enter both affect the output, so treat displayed decimals as indicative rather than exact.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
mi = km ÷ 1.609344; km = mi × 1.609344; nmi = km ÷ 1.852
- km
- Kilometres
- mi
- Statute miles
- nmi
- Nautical miles
- m
- Metres
Exact conversion factors; metres = km × 1000.
Frequently asked questions
Is a mile the same as a nautical mile?
No, and the gap is large enough to matter. A statute mile is about 1.609 kilometres; a nautical mile is about 1.852, chosen originally as one minute of latitude. Aviation and marine navigation use the nautical mile because it maps directly onto degrees on a chart, while road distances use the statute mile.
Is there a quick way to convert in my head?
Multiply by eight and divide by five, or for an approximate answer just multiply by 1.6. A neat trick for consecutive Fibonacci numbers is that they nearly correspond — five miles is about eight kilometres, and eight miles about thirteen. The approximation improves as the numbers grow, and breaks down for small values where rounding dominates.
Which inputs and limits apply to KM to Miles Converter?
Use the units shown beside each field. These are form limits, not recommended settings. Value: -1,000,000,000–1,000,000,000 1 international mile = 1.609344 km; 1 nautical mile = 1.852 km. Only the displayed unit definitions are converted; rounding and measurement uncertainty are separate.
What is a complete worked example for Value = 10; Direction = ⇄?
Inputs: Value = 10; Direction = ⇄; Decimal places = 4; From = Kilometres (km); To = Miles (mi). Calculation: mi = km ÷ 1.609344; km = mi × 1.609344; nmi = km ÷ 1.852. Results: Result = 6.2137 mi; In metres = 10,000 m; In nautical miles = 5.3996 nmi.