Convert Kilometer (km) (km) to Nautical mile (nmi) (nmi)
Category: Length
1 km = 0.539957 nmi
High-precision rounding: 6 decimals
How to convert kilometer (km) to nautical mile (nmi)
We convert by pivoting through the SI base unit for Length and applying exact factors where applicable.
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Quick conversion table
Handy values for Kilometer (km) → Nautical mile (nmi). Click a value to open that exact result.
Conversion formula
Linear unit conversions use standardized factors; many are exact by definition (e.g., 1 in = 25.4 mm, 1 ft = 0.3048 m).
Common mistakes
- Confusing international foot (0.3048 m) with legacy ‘US survey foot’ in old datasets.
- Rounding mid-calculation; keep precision to the end.
Unit facts
- Kilometer (km): One kilometer equals 1,000 meters; common for road distances and maps.
- Nautical mile (nmi): A nautical mile is exactly 1,852 meters—one minute of arc along a meridian. Basis for speed in knots.
About Length
Length measures distance or size. In SI it derives from the meter, defined via the speed of light, which ensures exact, reproducible conversions. Typical applications include construction, mapping, manufacturing tolerances, and navigation; legacy units like inches and feet remain common in trade and building plans.
About Kilometer (km)
Kilometer (km)
Equals 1,000 meters. Common for road distances, running events (5k/10k), and geographic scales. Convenient decimal multiple that keeps numbers human-readable.
History: Spread with metrication in the 19th–20th centuries. Adopted by most countries for signage and mapping, replacing miles in many contexts.
About Nautical mile (nmi)
Nautical mile (nmi)
Exactly 1,852 meters. Preferred in maritime and aviation because it links to Earth geometry (minutes of arc). Knots (nmi/h) derive from it.
History: Standardized by the International Hydrographic Organization in 1929; earlier definitions tied 1 nmi to 1 minute of latitude varying slightly with geodetic model.