About this calculator
It also shows the time for 5 km and 10 km at that pace, so you can set a treadmill for a target time.
How to use it
- Choose what you are converting from.
- Enter the pace or the speed.
- Read the result.
The formula
Speed (km/h) = 3600 ÷ pace (seconds per km)
- pace
- minutes and seconds per km
- speed
- kilometres per hour
Worked example
A pace of 5:30 per km
- Speed = 3600 ÷ 330 = 10.91 km/h, or 6.78 mph.
- 5 km takes 27:30 and 10 km takes 55:00.
What the result means
Treadmills often feel easier than running outside; a 1% incline is a common way to make up for it.
Assumptions
- Constant pace.
Limitations
- Treadmill calibration varies.
Frequently asked questions
What treadmill speed is a 6-minute km?
10 km/h.
Is 12 km/h fast?
It is a 5:00 per km pace, a good pace for most recreational runners.
How do I convert mph to km/h?
Multiply by 1.609.
Not medical advice. This calculator is a general screening tool and cannot diagnose any condition. Results are estimates. Please talk to a doctor or a qualified health professional about your health and before making changes to diet, exercise or treatment.
Last reviewed on 1 October 2026. Found a mistake? Tell us.