Speed Converter
Free online speed converter. Instantly convert km/h, mph, m/s, knots, ft/s, mach with real-time calculations.
How to convert km/h to mph?
Multiply km/h by 0.621371 to get mph. For example, 100 km/h ≈ 62.14 mph. The formula is: mph = km/h × 0.621371.
How to convert mph to km/h?
Multiply mph by 1.60934 to get km/h. For example, 60 mph ≈ 96.56 km/h. The formula is: km/h = mph × 1.60934.
What is a knot?
A knot is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h or about 1.15078 mph. It is widely used in maritime and aviation navigation.
What is the Mach number?
The Mach number is the ratio of an object's speed to the speed of sound in the surrounding medium. At sea level and 20°C, Mach 1 ≈ 343 m/s ≈ 1235 km/h ≈ 767 mph.
How to convert meters per second to km/h?
Multiply m/s by 3.6 to get km/h. For example, 10 m/s = 36 km/h. This is because 1 meter per second equals 3.6 kilometers per hour.
What is the speed of sound in different units?
At sea level and 20°C, the speed of sound (Mach 1) is approximately 343 m/s, 1235 km/h, 767 mph, or 667 knots.
How to convert knots to km/h?
Multiply knots by 1.852 to get km/h. For example, 100 knots = 185.2 km/h. One knot equals exactly one nautical mile per hour.
What are common speed units and their uses?
km/h is used for road traffic in most countries, mph in the US and UK, knots in maritime and aviation, m/s in physics and engineering, and Mach number for aircraft and spacecraft speeds.
What is the difference between speed and velocity?
Speed is a scalar quantity representing how fast an object moves, while velocity is a vector that includes both speed and direction. For example, 60 km/h is a speed, while 60 km/h north is a velocity.
Are my calculations private?
Yes, all calculations are performed entirely in your browser. No data is sent to any server, ensuring complete privacy and security.
How to Use Speed Converter
Convert speed units instantly in your browser: km/h, mph, m/s, knots, ft/s and Mach, with real-time results as you type. All calculations run locally — nothing is sent to a server.
- Type a value into the From field; the converted result appears in the To field immediately.
- Use the From dropdown to pick the unit of your input, for example km/h for a car speedometer.
- Pick the target unit in the To dropdown, such as mph, m/s, knots, ft/s or Mach.
- Swap the From and To units to run the conversion in the opposite direction and double-check the result.
One knot equals exactly 1.852 km/h — keep that anchor in mind to sanity-check aviation and marine conversions.
Related Tools
- Coordinate Format Converter Convert GPS coordinates between decimal degrees, DMS, DDM and GeoJSON instantly. Auto-detects the input format, handles N/S/E/W hemispheres, and exports batches as CSV — fully offline in your browser.
- Number Formatter Format numbers with thousands separators, decimal places, prefixes, and suffixes. Convert numbers to words in multiple languages instantly.
- Data Storage Converter Instantly convert between bytes, KB, MB, GB, TB, PB, bits, KiB, MiB, GiB. Supports decimal (SI) and binary (IEC) systems. Free, private & accurate.
- Color Converter Free online color converter. Convert HEX, RGB, HSL, HSV formats instantly with visual picker. 100% private, runs in your browser.
- Energy Converter Convert between Joule, Kilojoule, Calorie, Kilocalorie, Watt-hour, Kilowatt-hour, BTU, Electronvolt, and Foot-pound instantly.
- Frequency Converter Convert between Hz, kHz, MHz, GHz, THz, RPM, rad/s, BPM instantly. Free online frequency converter with real-time results.
- Angle Converter Convert between angle units: degree, radian, gradian, arcminute, arcsecond, revolution, milliradian, microradian.
- Pressure Converter Free online pressure converter. Instantly convert between Pa, kPa, MPa, bar, atm, PSI, Torr, mmHg and inHg with real-time calculations.