Speed
Speed Converter
Convert km/h, mph, knots, m/s, and more
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Input
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Conversion Formula
Target = Value × (From Ratio / To Ratio)
Speed conversions use linear ratios. Target = Value × (Source Ratio / Target Ratio). To convert km/h to mph: multiply by 0.277778 / 0.44704.
Speed conversion is useful in driving, aviation, sailing, and sports. Convert between km/h, mph, knots, m/s, and ft/s.
Knots are used in aviation and maritime contexts. One knot equals one nautical mile per hour (1.852 km/h).
All Supported Speed Units
| Unit | Symbol | Definition |
|---|---|---|
| Meter per second | m/s | The SI unit of speed, meters traveled per second. |
| Kilometer per hour | km/h | Kilometers traveled per hour, the standard road speed unit worldwide. |
| Mile per hour | mph | Miles traveled per hour, the road speed unit in the US and UK. |
| Knot | kn | One nautical mile per hour, used in aviation and maritime navigation. |
| Foot per second | ft/s | Feet traveled per second, used in engineering and physics. |
| Inch per second | in/s | Inches traveled per second, used in precision machinery. |
| Mach (Speed of Sound) | Ma | The ratio of speed to the speed of sound in air at sea level. |
Common Speed Conversions
| From | To | Value |
|---|---|---|
| 1 km/h | mph | 0.621 |
| 1 mph | km/h | 1.609 |
| 1 knot | km/h | 1.852 |
| 1 m/s | km/h | 3.6 |
Frequently Asked Questions
To convert kilometers per hour to miles per hour, multiply by 0.6214. For example, 100 km/h × 0.6214 = 62.14 mph. This is essential for international driving.
A knot is one nautical mile per hour. One knot = 1.15078 mph = 1.852 km/h. Knots are used in aviation and maritime navigation worldwide.
To convert meters per second to kilometers per hour, multiply by 3.6. For example, 10 m/s × 3.6 = 36 km/h. This is commonly used in physics and sports.
Mach number is the ratio of an object's speed to the speed of sound in the surrounding medium. Mach 1 equals approximately 343 m/s or 1,235 km/h at sea level.
One knot equals approximately 1.15078 miles per hour. To convert knots to mph, multiply by 1.151. For example, 20 knots ≈ 23 mph.
To convert miles per hour to kilometers per hour, multiply by 1.60934. For example, 60 mph × 1.609 = 96.56 km/h. This is useful for US drivers traveling abroad.
The speed of sound at sea level is approximately 1,235 km/h (767 mph) at 20°C. This varies with temperature, altitude, and atmospheric conditions.
Measurement Knowledge
Speed Reference Guides
Master speed measurements with our comprehensive educational resources.
Popular Speed Conversions
Direct access to the most commonly used conversion tools.
km/h Kilometer per Hour Conversions
mph Mile per Hour Conversions
m/s Meter per Second Conversions
kn Knot Conversions
ft/s Foot per Second Conversions
Supported Speed Units
Complete listing of available speed units in our converter.
km/h
Kilometer per Hour
metric
mph
Mile per Hour
imperial
m/s
Meter per Second
metric
kn
Knot
maritime
ft/s
Foot per Second
imperial