Speed Calculator
Calculate speed from distance and time. Results in m/s, km/h, and mph. Includes a speed reference table from walking to light speed.
SPEED
10 m/s
IN km/h
36 km/h
IN mph
22.3694 mph
FORMULA
v = d / t
Speed — Reference Table
| Speed | m/s | km/h | mph |
|---|---|---|---|
| Walking | 1.4 | 5.04 | 3.1317 |
| Running | 5 | 18 | 11.1847 |
| Cycling | 8.3 | 29.88 | 18.5666 |
| Car (city) | 13.9 | 50.04 | 31.0935 |
| Car (highway) | 31.3 | 112.68 | 70.0162 |
| Bullet train | 83.3 | 299.88 | 186.3371 |
| Sound (air) | 343 | 1,234.8 | 767.2704 |
| Light | 300,000,000 | 1,080,000,000 | 671,082,000 |
💡 How to Calculate Speed
What Is Speed?
Speed is a measure of how fast an object is moving. It is a scalar quantity, meaning it has magnitude but no direction — unlike velocity, which is a vector quantity with both magnitude and direction.
When someone says "the car is traveling at 60 mph," they are describing speed. If they say "the car is traveling at 60 mph north," they are describing velocity.
How to Calculate Speed
Speed Formula
Where speed is in m/s, distance in meters, and time in seconds. You can also use km and hours, or miles and hours, to get km/h or mph directly.
For example, if a runner covers 400 meters in 50 seconds: Speed = 400/50 = 8 m/s = 28.8 km/h = 17.9 mph.
Speed vs. Velocity
Velocity includes direction, while speed does not. If you drive 100 km north and then 100 km south in 4 hours, your average speed is 200/4 = 50 km/h, but your average velocity is 0/4 = 0 km/h because your displacement is zero.
Common Speed Conversions
- 1 m/s = 3.6 km/h = 2.237 mph
- 1 mph = 0.447 m/s = 1.609 km/h
- 1 km/h = 0.278 m/s = 0.621 mph