Convert km/h to kn

km/h
0.539956803456kn

1 km/h = 0.539956803456 kn

Type a value in kilometres per hour and the answer in knots appears as you go. The conversion is exactly 0.539956803456 kn to the kilometre per hour, and it happens on your own machine — this page asks nothing of a server once it has loaded.

  • Where it runs

    In your browser. The number you type is never part of a request.

  • Exact by definition

    1 km/h is exactly 0.539956803456 kn — a definition, not a rounded factor.

  • Answers as you type

    No button, no wait. The worked answer is already on the page before any script runs.

Kilometre per hour and Knot

Kilometres per hour is the speed limit almost everywhere in the world. Dividing by 3.6 gives metres per second, because there are 3,600 seconds in an hour and 1,000 metres in a kilometre.

A knot is one nautical mile per hour, and a nautical mile is exactly 1,852 metres — originally one minute of latitude, so a knot relates speed directly to position on a chart. Its name comes from counting knots in a rope paid out behind a ship.

kilometres per hour to knots in practice

  • 130 km/h is 70.19 kn

    — a motorway limit in much of Europe.

  • 5 km/h is 2.7 kn

    — walking pace.

kilometres per hour to knots at a glance

km/hkn
10.539956803456
21.07991360691
31.61987041037
52.69978401728
105.39956803456
2010.7991360691
5026.9978401728
10053.9956803456

Every figure here is computed from the same definition the calculator uses, so the table cannot drift away from the answer above it.

Convert km/h to kn: common questions

How many knots are in a kilometre per hour?

Exactly 0.539956803456. One kilometre per hour is 0.539956803456 knots, and the box above will do it for any figure you type.

Is this conversion exact, or rounded?

The ratio is exact. It is not a rounded constant typed into a table: it is derived from the definitions of the two units, so it agrees with any other correct converter to as many digits as you care to compare.

Why does another converter show a slightly different number?

Almost always rounding rather than disagreement. Many converters cut the answer to two or four decimals, and some carry a factor that was rounded before the multiplication rather than after. The figures here are computed from the exact definitions and only rounded on the way to the screen.

Where these figures come from

The claims this page makes about speed units are checkable, and these are the documents that settle them.

How this page works

The factor is a constant in the page and the arithmetic is four operations, so nothing is sent anywhere and nothing needs to be. The number you type never leaves the browser — there is no request for it to travel in.

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