Physics motion tool

Acceleration Calculator

Solve acceleration, initial velocity, final velocity, or time from three known motion values.

Enter three known values

Solve an acceleration problem

Free tool
m/s²

This is the value being calculated.

m/s

Velocity at the start of the interval.

m/s

Velocity at the end of the interval.

s

Duration over which velocity changes.

Use meters per second for velocity, seconds for time, and meters per second squared for acceleration.

Try an example:

Your acceleration result will appear here

Choose the missing variable and enter the other three values.

Motion analysis

What is acceleration?

Acceleration is the rate at which velocity changes with time. It can describe speeding up, slowing down, or changing direction.

Formula

Acceleration formula

Accelerationa = (v − u) ÷ t

  • a is acceleration.
  • u is initial velocity.
  • v is final velocity.
  • t is elapsed time.

Worked example

Velocity increases from 5 m/s to 25 m/s in 4 seconds

  1. Velocity change: 25 − 5 = 20 m/s.
  2. Divide by time: 20 ÷ 4 = 5 m/s².
  3. The acceleration is 5 m/s².

Direction and signs

What does negative acceleration mean?

Negative acceleration means the velocity change is negative relative to the chosen positive direction. It does not always mean an object is slowing down; the result depends on the signs of velocity and acceleration.

Rearranged equations

Solve for other motion variables

Initial velocity

u = v − at

Subtract acceleration multiplied by time from final velocity.

Final velocity

v = u + at

Add acceleration multiplied by time to initial velocity.

Time

t = (v − u) ÷ a

Divide velocity change by non-zero acceleration.

Units

Keep motion units consistent

This calculator uses meters per second for velocity, seconds for time, and meters per second squared for acceleration. Convert other units before calculating.

Assumptions

When this formula applies

  • It calculates average acceleration over the selected interval.
  • It is exact for constant acceleration.
  • Time must be greater than zero.
  • Direction must be represented consistently with positive and negative signs.

Related tools

Use the Rate of Change Calculator for general two-point change calculations, or the Linear Regression Calculator to find the slope of a complete dataset.

Review the Tables and Graphs Guide for presenting velocity and time data.

Related calculators

Questions and answers

Acceleration calculator FAQ

What formula does the acceleration calculator use?

It uses a equals final velocity minus initial velocity divided by time: a = (v − u) ÷ t.

Can acceleration be negative?

Yes. Negative acceleration means velocity decreases in the selected positive direction.

What units should I use?

Use meters per second for velocity, seconds for time, and meters per second squared for acceleration.

Does this calculator assume constant acceleration?

Yes. The formula applies to average acceleration across the interval and is exact for constant acceleration.

Accuracy and transparency

Created and maintained by our editorial team

This physics calculator is maintained by the Science Lab Tools Editorial Team. Its calculation logic is tested with representative inputs, while the supporting guidance is checked for formula clarity, units, assumptions, and common mistakes.

Learn more about our formula-review and correction process, or read about Science Lab Tools.

  • Calculation logic tested
  • Variables and units explained
  • Assumptions stated clearly
  • Corrections handled transparently