Speed Converters
How fast something is going — km/h, mph, m/s and knots.
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What speed units measure
Speed units measure how much distance is covered in how much time. Because both halves are fixed — a mile is a fixed distance, an hour a fixed time — every conversion between them is one fixed number, exactly like weight or length. 1 mph is exactly 1.609344 km/h, the same ratio as a mile to a kilometer.
Speed units on this site
| Unit | Symbol | Equals in kilometers per hour |
|---|---|---|
| Kilometers per hour | km/h | 1 (base unit) |
| Miles per hour | mph | 1.609344 |
| Meters per second | m/s | 3.6 |
| Knots | kn | 1.852 |
Every converter here calculates through kilometers per hour, so a pair and its reverse always agree. The full list of factors and the standards behind them is on the methodology page.