Convert nautical mile to kilometer.

Convert nautical mile (nmi) to kilometer (km). This is a fixed-ratio conversion — multiply the input by the factor below.

Formula

km = nmi × 1.852

Reference values

Things to watch for

• The international inch is exactly 25.4 mm (defined since 1959), so length conversions are exact, not approximations.
• Use mm for engineering drawings, cm for everyday measurements, m for room dimensions, km for distances.
• 1 mile = 1.609344 km (exact). Nautical miles are different: 1 nmi = 1852 m exactly (defined for nautical use).

What is a nautical mile?

One nautical mile equals exactly 1,852 meters — approximately one minute of arc of latitude on the Earth's surface. Maritime navigation, aviation, and any application where geographic positioning matters.

What is a kilometer?

One kilometer equals exactly 1,000 meters. Road distances, geographic distances, marathon running, and everyday long-distance measurement worldwide except in the US, UK and a few other countries.

How big is one nmi in real terms?

To put the unit in perspective, here are a few real-world examples. 1 nmi is about 1.15 statute miles; 60 nmi is about one degree of latitude on Earth.

How to convert nautical mile to kilometer

To convert a value from nautical mile (nmi) to kilometer (km), apply the conversion factor shown in the formula above. The calculation is the same whether you do it by hand, in a spreadsheet, or with the live converter on this page.

Steps:

1. Take your input value in nmi.
2. Apply the formula km = nmi × 1.852.
3. The result is your value in km.

For repeated calculations, save the formula in a spreadsheet or use the live converter at the top of this page — it handles the math automatically and displays the result as you type.

Frequently asked questions

How do I convert nmi to km?

Apply the formula nmi → km shown above, or just type your value into the converter at the top of this page. The result updates instantly.

Which is bigger, nmi or km?

This depends on the conversion ratio in the formula. If the factor multiplied by your value gives a larger number, then km is the smaller unit (so it takes more of them to express the same quantity). If the result is smaller, then km is the larger unit.

When would I use nmi versus km?

Both units measure length, so the choice depends on context. Nautical mile is typically used for engineering specs, construction, navigation, and everyday measurement; kilometer similarly. Most professional fields standardize on one or the other based on regional conventions or technical tradition.

How precise is this nmi to km conversion?

The conversion factor shown is the internationally defined exact value (or the best-published approximation if the relationship is irrational, like degrees-to-radians). The live converter on this page uses double-precision floating-point math, accurate to about 15 significant digits — far beyond any practical engineering need.

Is the conversion ratio exact, or an approximation?

Most unit conversions between SI metric units, and between SI and US customary units, have been formally defined as exact values since the 1959 international yard-pound agreement and subsequent SI redefinitions. Exceptions are unit pairs that involve irrational numbers (radians, e.g.) or empirical conversions (like food calories, which depend on temperature). When in doubt, consult the formula at the top of this page.

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See also