mph to knots converter
This mph to knots converter turns miles per hour into knots as you type, so a wind speed from a phone forecast, a hurricane report on the news or a drone limit reads the way sailors and pilots count it.
Formula: kts ≈ M/h ÷ 1.15078 30 ÷ 1.15078 ≈ 26.06928726
Using the mph to knots converter
Put the mph value in the field and the knots show up on the right. The page starts on 30 mph, displayed as 26.0693 knots, a breezy afternoon on a weather app. Decimals such as 12.5 work as typed. Switch the units with the round button, or open the page that goes from knots back to miles per hour. Below the result, the same speed appears in km/h, feet per second and every other speed unit.
To go from mph to knots, multiply by 0.868976, or divide by 1.150779. Both numbers come from two exact lengths: the statute mile of 5,280 feet, or 1,609.344 meters, and the international nautical mile of 1,852 meters, as listed by NIST. Since 1,609.344 ÷ 1,852 = 0.868976, converting miles per hour to knots always trims a speed by about 13 percent. The mph to knots converter keeps every decimal of that ratio.
Mental shortcut: take away one eighth. 48 mph minus 6 gives 42 knots, close to the exact 41.71, and 16 mph becomes 14 knots. If a boat speedometer reads mph while the chart works in knots, the shortcut gives a first idea and the converter settles the decimals.
Common values
| M/h | kts |
|---|---|
| 1 | 0.869 |
| 5 | 4.3449 |
| 10 | 8.6898 |
| 15 | 13.0346 |
| 20 | 17.3795 |
| 25 | 21.7244 |
| 30 | 26.0693 |
| 40 | 34.759 |
| 50 | 43.4488 |
| 60 | 52.1386 |
| 74 | 64.3042 |
| 100 | 86.8976 |
Sailing, storms, drones and older aircraft
Sailors and kiteboarders think in knots, while phone weather apps set to US units show wind in mph. A forecast of 18 mph means 15.6 knots and 25 mph means 21.7 knots, the unit that sailing guides and kite size charts use. The mph to knots converter bridges the two before you leave the dock.
News reports give hurricane winds in mph, while marine forecasts work in knots and the National Hurricane Center scale lists both. Category 3, the first major hurricane level, starts at 111 mph, which the mph to knots converter puts at 96.5 knots; the official scale rounds it to 96 knots. A 45 mph gust in a TV forecast is 39.1 knots in the same terms.
Drone pilots meet the same pair: the FAA rule for small drones caps groundspeed at 87 knots, written next to 100 mph, and by the math 100 mph is 86.9 knots. Some older light aircraft have airspeed indicators in mph while charts and controllers work in knots, so an mph to kts check is part of flight planning. To read the same speed in km/h, use the mph to km/h converter.