How to use Speed Converter
Type any speed value into its field and all other units update instantly. The converter handles knots, miles per hour (mph), kilometers per hour (km/h), meters per second (m/s), and feet per second (ft/s). Use the Beaufort Scale reference table below the converter to interpret wind speed readings, or click any row to load that reference speed into the converter.
Why use UtilDaily’s Speed Converter?
- Speed units are not interchangeable across industries. Aviation and maritime use knots, US road signs use mph, and most countries use km/h — this converter handles all five simultaneously.
- Eliminates chained conversions (knots → km/h → mph) that introduce rounding errors at each step.
- The Beaufort reference table adds practical context for interpreting wind speed readings from weather reports and marine forecasts.
Frequently Asked Questions
How do I convert knots to mph?
Multiply knots by 1.15078 to get mph. For quick mental math, add about 15% to the knot value. Examples: 10 knots = 11.5 mph, 20 knots = 23.0 mph, 50 knots = 57.5 mph, 100 knots = 115.1 mph. To go the other direction, divide mph by 1.15078 (or multiply by 0.868976) to get knots.
Why do ships and planes use knots instead of mph?
A nautical mile equals exactly one minute of latitude on the Earth's surface. This makes navigation math much simpler: traveling 60 nautical miles due north moves you exactly 1 degree of latitude. Because aeronautical charts use nautical miles, aviation adopted knots from maritime tradition. The standardization means a pilot and a ship captain use the same speed unit, reducing communication errors in shared airspace and harbor approaches.
How do I convert km/h to mph?
Multiply km/h by 0.621371 to get mph, or divide by 1.60934. For a quick estimate, multiply by 0.6 (accurate to within 3%). Examples: 100 km/h = 62.1 mph, 120 km/h = 74.6 mph, 50 km/h = 31.1 mph. Going the other way: multiply mph by 1.60934 to get km/h.
What is a meter per second in mph?
One meter per second equals 2.23694 mph. To convert m/s to mph, multiply by 2.237. For example, 10 m/s = 22.37 mph, 30 m/s = 67.1 mph. Scientific measurements often use m/s, especially for wind speed in meteorology and physics problems.
How fast is hurricane wind speed in mph and km/h?
A hurricane starts at sustained winds of 64 knots (74 mph / 119 km/h) on the Beaufort scale Force 12. Category 1 hurricanes range from 64-82 knots (74-95 mph / 119-153 km/h). Category 5 hurricanes exceed 137 knots (157 mph / 252 km/h). Wind speeds in weather reports are usually given in knots for marine forecasts, mph for US broadcasts, and km/h for international and Canadian broadcasts.
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