Aviation mixes unit systems freely: distances in nautical miles, speeds in knots, altitudes in feet, fuel in litres or kilograms, and visibility in metres or statute miles depending on the country. This converter handles the standard relationships in one place, using the exact international definitions.
How this calculator works
Conversions use internationally standard unit relationships.
Worked example
500 nautical miles is exactly 926 km, or about 575 statute miles. 150 knots is 278 km/h or 173 mph. 10,000 ft is 3,048 m. The relationships are fixed by definition, so the conversions are exact rather than estimates.
Frequently asked questions
Why does aviation use nautical miles and knots?
One nautical mile equals one minute of latitude, which makes distances measurable directly on a chart with dividers, and one knot is simply one nautical mile per hour. The system predates aviation — it was inherited from marine navigation because the geometry works anywhere on Earth.
How long is a nautical mile exactly?
Exactly 1,852 metres by international definition — about 1.151 statute miles. A statute mile is 1,609.344 metres, so the two differ by roughly 15%, which matters when converting visibility or range figures between European and US publications.
Which countries use metres for altitude?
China, Mongolia and parts of Central Asia assign flight levels in metres; Russia moved to feet at higher levels in recent years but kept metric procedures lower down. Everywhere else altimetry runs in feet, which is why cross-border metric conversion remains a live skill for ferry and airline pilots.
What to verify next
- Approved aircraft documentation and current limitations.
- Local fuel, insurance, maintenance, hangar and financing quotations.
- The exact aircraft configuration, loading and maintenance status.