Acceleration Calculator
Solve acceleration, velocity, time, force or mass from a = (v − u) / t and F = m·a, with instant unit conversions.
From a change in velocity a = (v − u) / t
- Acceleration
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- In g-force
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- In ft/s²
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- In km/h per second
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- Change in velocity (Δv)
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- Time taken
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- Distance covered
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- Average velocity
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From force and mass F = m × a
- Acceleration
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- In g-force
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- Force
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- Mass
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Formulas used
- a = (v − u) / t
- v = u + a·t
- t = (v − u) / a
- s = u·t + ½·a·t²
- F = m·a
- 1 g = 9.80665 m/s²
How it works
Acceleration is how fast a velocity changes, so the calculator works from the standard constant-acceleration formula a = (v − u) / t. Pick which quantity you are missing, type the other three, and the answer appears as you type — no Calculate button. Every value is converted to SI units first (metres per second, seconds, metres per second squared), so you can mix km/h with seconds or mph with minutes and still get a correct result. The answer is shown in m/s², in ft/s², in km/h per second and in g-force, where 1 g is the 9.80665 m/s² of Earth's gravity — handy for checking a 0–100 km/h sprint time or a lift's comfort limit.
The second block applies Newton's second law, F = m × a, so you can go from force and mass to acceleration or back again, with newtons, kilonewtons, pounds-force, kilograms, pounds and tonnes all supported. Distance covered and average velocity assume the acceleration is constant over the whole interval, which is the usual physics-homework assumption; real vehicles vary. Everything is calculated by JavaScript inside your own browser — no upload, no account, no ads — and you can copy the full breakdown or download it as a plain text file.
Frequently asked questions
How do you calculate acceleration from velocity and time?
Subtract the starting velocity from the final velocity and divide by the time it took: a = (v − u) / t. A car going from 0 to 100 km/h in 5 seconds gains 27.7778 m/s of velocity, so its acceleration is 27.7778 ÷ 5 = 5.5556 m/s². Type any three of u, v, t and a into the calculator and it solves the fourth instantly, converting km/h, mph, ft/s, knots, minutes and hours to SI units first so you can mix units freely.
What is 1 g and how do I convert m/s² to g-force?
One g is the acceleration of Earth's gravity, defined as 9.80665 m/s², so you convert by dividing your answer in m/s² by 9.80665. That 0–100 km/h in 5 seconds sprint works out at 0.5665 g. The calculator prints the answer in m/s², ft/s², km/h per second and g at the same time, and you can also type a value straight into the acceleration box in g and read the other units back.
Can it work out force or mass with F = ma?
Yes. The second block applies Newton's second law: choose whether you are missing the acceleration, the force or the mass, and the other two solve it. A 1000 N force on a 200 kg object gives 5 m/s². Force accepts newtons, kilonewtons, pounds-force and kilograms-force, and mass accepts kilograms, grams, tonnes and pounds. Everything runs in your own browser — nothing is uploaded, there are no ads and no sign-up — and you can copy or download the whole breakdown as a text file.