How to Convert Nautical miles to Miles (nmi to mi)
Length conversions come up when reading overseas furniture specs, cycling the Round Island Route in kilometres while a foreign app shows miles, or checking marine distances in the Singapore Strait in nautical miles. This guide shows how to convert nautical miles into miles by hand, with examples and a quick-reference table.
The conversion
To convert nautical miles to miles, multiply the value by 1.150779448. To go the other way, divide by the same number (or multiply by 0.8689762419). For a quick estimate, multiply by about 1.2.
Miles = nautical miles × 1.150779448
Worked examples
- 3 nmi = 3.4523 mi
- 12.5 nmi = 14.3847 mi
- 75 nmi = 86.3085 mi
Nautical miles to Miles table
| Nautical miles | Miles |
|---|---|
| 1 nmi | 1.1508 mi |
| 2 nmi | 2.3016 mi |
| 5 nmi | 5.7539 mi |
| 10 nmi | 11.5078 mi |
| 20 nmi | 23.0156 mi |
| 25 nmi | 28.7695 mi |
| 50 nmi | 57.539 mi |
| 100 nmi | 115.0779 mi |
| 250 nmi | 287.6949 mi |
| 500 nmi | 575.3897 mi |
| 1,000 nmi | 1,150.78 mi |
Common questions
Is nmi to mi exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Miles to Nautical miles converter.
Mistakes to avoid
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
For any value, use the Nautical miles to Miles Converter or browse all length converters.
Run your own numbers: Nautical miles to Miles Converter