Speed, Distance & Time

Solve kinematics formulas for travel speed, distance covered, or time required.

Calculate For

Distance

Time

Speed

75 km/h or mph

Guide & Educational Reference

How to Use the Speed, Distance & Time Calculator

1Choose what to Calculate For: Speed (v = d / t), Distance (d = v × t) or Time (t = d / v).
2Enter the two known values. The calculator shows only the fields it needs for the selected mode.
3Keep your units consistent — for example distance in km and time in hours.
4Read the calculated Speed, Distance or Time below, rounded to two decimals.

What This Calculator Solves

The Speed, Distance & Time Calculator solves the basic motion relationship v = d / t for whichever of the three quantities you leave unknown. Pick a mode, enter the other two values, and it returns the third. It is useful for trip planning, running or cycling splits and physics homework. The tool works with whatever units you supply and does not convert them: the result is expressed in the matching compound unit — the distance unit divided by the time unit.

Formulas by Mode

Speed mode

Active when 'Calculate For' is set to Speed. Needs Distance and Time.

Speed = Distance ÷ Time

Distance mode

Active when 'Calculate For' is set to Distance. Needs Speed and Time.

Distance = Speed × Time

Time mode

Active when 'Calculate For' is set to Time. Needs Distance and Speed.

Time = Distance ÷ Speed

Practical Real-World Examples

Average speed over a 150-mile drive taking 2 hours (Speed mode)

Speed = 150 ÷ 2 = 75

→ 75.00 — miles per hour, because the inputs were miles and hours

Distance covered at 60 km/h for 2.5 hours (Distance mode)

Distance = 60 × 2.5 = 150

→ 150.00 km

Time to cover 150 km at 75 km/h (Time mode)

Time = 150 ÷ 75 = 2

→ 2.00 hours

Tips & Considerations

Units are not converted. Enter km and hours and you get km/h; enter metres and seconds and you get m/s. Mixing units (km with minutes) gives a meaningless number.
In Speed mode a Time of 0 returns 'Division by zero is undefined', because dividing distance by zero time has no answer.
In Time mode a Speed of 0 is likewise undefined — an object that never moves never arrives.
Distance must be positive in Speed and Time modes; negative values are rejected.
Results are rounded to two decimal places for display; the underlying division is exact.
This is average speed over the whole trip, not the instantaneous speed at any moment.

Frequently Asked Questions

What is the difference between speed and velocity?

Speed is how fast something moves; velocity is speed together with a direction. This calculator works with speed, a single positive magnitude.

What units should I use?

Any consistent pair — kilometres and hours, miles and hours, metres and seconds. The result takes the matching compound unit. The tool never converts between systems.