Speed, Distance, Time Formula
Calculate speed, distance, or travel time when you know the other two.
The most basic and useful navigation formula.
The Formula
d = s × t | s = d / t | t = d / s
These three forms of the same relationship let you find any one value when you know the other two. They apply to any constant-speed motion — driving, flying, sailing, running, or cycling.
Variables
| Symbol | Meaning |
|---|---|
| d | Distance traveled (km, miles, meters, etc.) |
| s | Speed (km/h, mph, m/s, etc.) |
| t | Time taken (hours, minutes, seconds, etc.) |
Example 1
A car travels at 90 km/h for 2.5 hours. How far does it go?
d = 90 × 2.5
d = 225 km (about 140 miles)
Example 2
A flight covers 3,600 km in 4 hours. What is the average speed?
s = 3,600 / 4
s = 900 km/h (about 559 mph)
When to Use It
Use the speed-distance-time formula when:
- Estimating travel time for road trips or flights
- Calculating average speed from distance and time
- Planning routes and departure times
- Converting between different speed units