Speed, Distance & Time Calculator
Enter any two of speed, distance, and time to instantly solve for the third, using the standard distance-rate-time relationship.
Time
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Enter your known values to calculate.
How the Speed, Distance & Time formula works
The three rearrangements of the same relationship:
Distance = Speed × Time Speed = Distance / Time Time = Distance / Speed
Step-by-step calculation
- Identify which two values you know: speed, distance, or time.
- Use the rearrangement of the formula that solves for the missing third value.
- Make sure units are consistent (e.g., speed in mph pairs with distance in miles and time in hours).
Worked example
Traveling 150 miles at 60 mph: Time = 150/60 = 2.5 hours. Traveling for 3 hours at 45 mph: Distance = 45 × 3 = 135 miles.
Frequently asked questions
Do the units need to match?
Yes — speed, distance, and time need consistent units for the formula to work correctly (for example, speed in miles per hour requires distance in miles and time in hours, not minutes).
Does this work for any kind of motion, not just vehicles?
Yes — the distance-rate-time relationship applies to any constant-speed motion, from walking pace to data transfer rates, as long as the 'speed' is genuinely constant over the period being calculated.