Velocity Calculator
Enter the starting velocity, the acceleration and the time to find the final velocity.
This result is an estimate only. Double-check important figures before relying on them.
How it is calculated
- Final velocity = u + a × t
- Distance = u × t + ½ × a × t²
- Average velocity = (u + v) ÷ 2
For a simple trip, use the speed, distance and time calculator.
Worked example
Starting from rest, accelerating at 3 m/s² for 4 s:
- v = 0 + 3 × 4 = 12 m/s (43.2 km/h)
- Distance = ½ × 3 × 16 = 24 m
Why your number may differ
The formulas assume a constant acceleration in a straight line. Real vehicles lose acceleration as they speed up.
Frequently asked questions
What is the formula for final velocity?
v = u + at, where u is the initial velocity, a the acceleration and t the time. It holds when the acceleration is constant.
How is the distance found?
Distance = ut + ½at², which is also the average velocity times the time.
What if the object slows down?
Enter a negative acceleration. If the result goes below zero, the object has stopped and then reversed.