# Speed Calculator

> Calculate average speed from distance and time, or the distance covered or time taken, in km/h, mph, m/s or knots, with times shown as h:mm:ss.

Category: Everyday tools · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/speed-calculator

Average speed is distance divided by time. Rearranged, distance = speed × time and time = distance ÷ speed.

Also called: Speed distance time calculator, Average speed calculator, Velocity calculator.

## Inputs
- Solve for (options: Speed, Distance, Time; default speed)
- Distance (default 100)
- Distance unit (options: kilometres, miles, metres, nautical miles; default km)
- Time: hours (default 1; optional)
- Time: minutes (default 15; optional)
- Time: seconds (default 0; optional)
- Speed (default 80)
- Speed unit (options: km/h, mph, m/s, knots; default kmh)

## Results
- Answer
- Speed
- Speed
- Speed
- Distance
- Distance
- Time (h:mm:ss)
- Time in hours

## Formula

```
Speed = Distance ÷ Time;  Distance = Speed × Time;  Time = Distance ÷ Speed
```

Where:
- Distance: converted to km (1 mile = 1.609344 km, 1 nautical mile = 1.852 km)
- Time: hours + minutes ÷ 60 + seconds ÷ 3600
- Speed: converted to km/h (1 m/s = 3.6 km/h, 1 knot = 1.852 km/h)

## Worked example
1. Time = 1 h + 15 ÷ 60 h = 1.25 h.
2. Speed = 100 km ÷ 1.25 h = 80 km/h.
3. 80 ÷ 1.609344 = 49.71 mph.

**Result:** Covering 100 km in 1 hour 15 minutes is an average of 80 km/h, or 49.71 mph.

## What the result means

The result is an average over the whole trip: stops and slow sections are included in the time, so the average is usually well below the speeds you actually drove.

## Assumptions and limits
- Distance and time are for the same journey, including any stops you want counted.
- Gives average speed, not instantaneous speed or a route-specific travel time.

## Questions

### Why is my average speed lower than my cruising speed?

Average speed divides the whole distance by the whole time. Ten minutes stopped on a one-hour trip cuts the average by about a sixth.

### How do I convert km/h to m/s?

Divide by 3.6. For example, 90 km/h ÷ 3.6 = 25 m/s.

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Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/speed-calculator