Wind Speed Converter — Knots to mph, km/h, m/s & Beaufort

Converter

Drag, type, done.

Cheat sheet

Wind speed conversion table

The speeds riders actually care about, in every unit at once.

Knots	mph	km/h	m/s	Beaufort	Feels like
5 kt	5.8	9.3	2.6	F2	Leaves rustle — paraglider weather
8 kt	9.2	14.8	4.1	F3	Flags extend — sailboats move properly
10 kt	11.5	18.5	5.1	F3	Constant breeze — big-wing foiling starts
12 kt	13.8	22.2	6.2	F4	Small whitecaps — light-wind kites work
15 kt	17.3	27.8	7.7	F4	Whitecaps everywhere — kite session is on
18 kt	20.7	33.3	9.3	F5	The sweet spot for most kitesurfers
20 kt	23.0	37.0	10.3	F5	Powered riding on mid-size kites
25 kt	28.8	46.3	12.9	F6	Strong — small kites, spray off the water
30 kt	34.5	55.6	15.4	F7	Experts only, walking gets hard
35 kt	40.3	64.8	18.0	F8	Gale — most riders stay on the beach
40 kt	46.0	74.1	20.6	F8–9	Storm riding, professional territory

The formulas

How the conversions work

Every conversion runs off the knot, which is defined as exactly 1.852 km/h (one nautical mile per hour). From there: 1 knot = 1.15078 mph = 0.51444 m/s. The handy mental shortcuts: knots to mph, add 15%; knots to km/h, double it and knock a bit off; knots to m/s, halve it.

The Beaufort scale isn't a unit — it's a 0–12 force scale that maps wind speed to what you can see: F4 makes whitecaps, F6 makes spray, F8 makes you regret launching. Forecast apps mix all four units freely (Windguru defaults to knots, many European spot guides use m/s, US forecasts love mph), which is exactly why this page exists. For the full scale with sea states, see our Beaufort scale guide, or the printable chart in knots to mph & km/h.

Once the units make sense, the next question is whether today's number is your number — that's what the kite size calculator and wing size calculator answer.

Questions

Converter FAQ

How many mph is 1 knot?

1 knot = 1.15078 mph. A knot is one nautical mile per hour, and a nautical mile (1,852 m) is longer than a statute mile (1,609 m), so the mph number is always about 15% bigger. Quick head math: take the knots, add 15%. 20 knots ≈ 23 mph.

How do I convert knots to km/h?

Multiply by 1.852 — a knot is exactly 1.852 km/h by definition. So 10 knots is 18.5 km/h, 20 knots is 37 km/h, and 30 knots is 55.6 km/h. Going the other way, divide the km/h figure by 1.852, or just halve it for a rough first guess.

Why do wind forecasts use knots?

Knots come from navigation: one knot is one nautical mile per hour, and a nautical mile is one minute of latitude, which makes wind, boat speed and chart distances line up neatly. Sailing, aviation and marine forecasting all standardised on it, and wind sports inherited the habit.

What is a good wind speed in knots for wind sports?

Most kitesurfers want 15–25 knots, windsurfers 15–30, wing foilers 12–22, and sailors are happy from about 8 knots. Below 10 knots most wind sports stall; above 30 it's experts only. Paragliders are the exception — they fly in 5–15 knots and land before it gets wild.

Know your number? Get pinged when the wind hits it.

The free WindUp app watches live stations and rings — even on silent — the moment your spot crosses your threshold. In knots, mph, km/h or m/s.

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Wind speed converter: knots, mph, km/h, m/s.

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