Example 1
Cruise control 113 km/h (31.3 m/s) for 1.5 h: how far?
Uniform Motion Calculator
Enter any two of three: speed, distance, time. The calculator computes the missing one from s = v·t at constant v. 33.3 m/s for 3600 s is about 120,000 m, or 120 km of driving with no stops.
Result
Speed v, Distance s and Time t. The result shows up here.
How it works
Uniform motion is constant speed: s = v·t, v = s/t, t = s/v. 120 km/h is 33.3 m/s. Over 3600 s that is about 120,000 m, or 120 km. You type two fields and leave the third as the unknown. At 6 m/s over 36,000 m the time is 6000 s. At 8 m/s over 480 m the time is 60 s.
Speed and distance take units from the labels. Time is in seconds unless the label says otherwise. An hour is 3600 s, not 1. 120 in a m/s speed field is 120 m/s, over 400 km/h, not one hundred twenty on the dial. A comma and a period are the same v: 33,3 and 33.3.
Exactly two fields need a number. Three filled fields are rejected, because the calculator cannot tell what to solve. Two unknowns are not enough. Zero speed with a nonzero distance does not give a finite time: you never arrive. Typed 0 in s with a nonzero v gives t = 0.
Acceleration and average speed with stops live next door. Here v does not drop at lights. The sibling card only does s = v·t; here you can also get v or t. Kinetic energy ½mv² is another story: distance here, not joules.
The English card’s 31.3 m/s for 5400 s (1.5 h) is about 169 km. A 240,000 m stretch in 4320 s is a steady about 55.6 m/s. Type those example pairs and match the notebook.
Pick the unknown, fill the other two, click Calculate. 33.3 and 3600 give about 120,000 m. The header symbol does not drive for you. You pick the Missing quantity, then type the rest.
Distance only at constant v: s = v·t. With stops: average speed.
How to use
- Decide what you want: v, s, or t. Leave that field as the unknown. The calculator computes that one quantity.
- Type the other two. Distance example: v = 33.3 m/s and t = 3600 s. 120 km/h is about 33.3 m/s, not 120 in a m/s field.
- Click Calculate. The missing distance is about 120,000 m, or 120 km. At 8 m/s and 480 m the missing time is 60 s.
- Do not type all three: the calculator cannot tell what to solve. Two unknowns are not enough. Zero in v with nonzero s does not give a finite t.
- With stops, open average speed. Distance-only s = v·t is on the neighbouring page. Here v is constant and you can also get v or t.
Formula
s = v · t
Also v = s / t and t = s / v. Two fields filled, the third empty.
s, v, and t at constant speed
Uniform motion in this calculator wants two fields filled and one blank. s = v·t, so also v = s/t and t = s/v, no acceleration.
- s
- Distance. At constant v it is the product v·t. Blank s means: compute distance from the other two.
- v
- Constant speed. Typed 0 is a stop, not unknown. Blank v is the unknown.
- t
- Time. Zero seconds does not divide when you compute v = s/t. Two blanks are too few inputs.
- Missing quantity
- The calculator result: the one of three you did not type. Fill exactly two fields.
Real-life examples
Example 2
A 240000 m stretch in 1 h 12 min: what constant speed?
Example 3
36000 m of flat road at 6 m/s: how long?
Example 4
Steady 8 m/s over 480 m, travel time?
Example 5
9000 m in 45 min: what speed?
Example 6
Pace 4 m/s for 12.5 min: distance?
Example 7
22000 m at a steady 12 m/s: time?
Example 8
250 m/s for 40 min: distance covered?
Ways to use this calculator
- You find kilometers at a steady 33.3 m/s for an hour.
- You check time for 1000 m at constant v.
Frequently asked questions
How much distance at 33.3 m/s for 3600 s?
s = 33.3 × 3600 ≈ 120,000 m, or 120 km. 120 km/h is about 33.3 m/s. At 31.3 m/s for 5400 s you get about 169 km on the English page.
How many fields do I fill?
Exactly two. The third is the unknown. Three numbers at once are rejected, because the calculator cannot tell which quantity to solve.
Which units do I type?
The labeled ones. v is often m/s. 120 km/h is 33.3 m/s, not 120 in a m/s field. Time is usually seconds: an hour is 3600.
How is a blank field different from zero?
Blank is the unknown. Typed 0 in v with nonzero s does not give a finite t. Typed 0 in s gives t = 0.
Where is average speed with stops?
On the average-speed page. Here v does not drop at lights. This calculator assumes one constant speed.
How is this different from the distance-only tool?
That page only does s = v·t. Here you can also get v or t, as long as you fill exactly two fields.
Does a comma in 33.3 work?
Yes. 33,3 and 33.3 are the same speed. The calculator does not require a period.
Where is acceleration?
On the acceleration page or accelerated motion. Here a = 0. Speed does not rise or fall.
Is 120 in the v field 120 km/h?
Only if the label is km/h. In m/s that is 120 m/s, over 400 km/h. Convert 120 km/h to 33.3 m/s first.
How much time for 480 m at 8 m/s?
t = 480 / 8 = 60 s. For 36,000 m at 6 m/s that is 6000 s. Both pairs sit on the example cards.
Knowledge sources
The formula is the school one. Units follow SI; NIST SP 330 and BIPM define the measures, not your result.
Page updated in 2026.