Acceleration Converter
Convert any acceleration between m/s², ft/s², standard gravity (g), Gal, milligal, km/h per second, mph per second and more. Switch to the 0–60 mode to turn a car's 0–60 mph or 0–100 km/h time into its average g-force.
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How to use the Acceleration Converter
- Choose a mode: convert units, or turn a 0–60 time into g-force.
- Enter the value and pick the From and To units.
- Press Convert to see the result plus the same value in every unit.
- For cars, enter the 0–60 mph (or 0–100 km/h) time to get average acceleration, mph per second and launch distance.
- Copy the result or download the table as CSV.
Acceleration conversion formula
Every conversion goes through the SI unit, meters per second squared. Multiply by the factor of the unit you start with, then divide by the factor of the unit you want:
value in target unit = value × (m/s² per source unit) ÷ (m/s² per target unit)
Worked example: an elevator accelerates at 4.5 ft/s². 4.5 × 0.3048 = 1.3716 m/s², and 1.3716 ÷ 9.80665 = 0.14 g, so riders feel about 14% heavier while it speeds up.
Acceleration unit factors
| Unit | Symbol | In m/s² | Units per 1 g |
|---|---|---|---|
| Meters per second squared | m/s² | 1 | 9.80665 |
| Feet per second squared | ft/s² | 0.3048 | 32.174 |
| Standard gravity (g-force) | g | 9.80665 | 1 |
| Gal (centimeters per second squared) | Gal | 0.01 | 980.665 |
| Milligal | mGal | 1e-05 | 980665 |
| Kilometers per hour per second | km/h/s | 0.277778 | 35.3039 |
| Miles per hour per second | mph/s | 0.44704 | 21.9369 |
| Inches per second squared | in/s² | 0.0254 | 386.089 |
| Millimeters per second squared | mm/s² | 0.001 | 9806.65 |
| Knots per second | kn/s | 0.514444 | 19.0626 |
Standard gravity is fixed by definition at exactly 9.80665 m/s². Actual gravity varies slightly with latitude and altitude, from about 9.78 m/s² at the equator to 9.83 m/s² at the poles.
Typical accelerations for comparison
| Situation | Approximate g | m/s² |
|---|---|---|
| Passenger train or subway pulling away | 0.05–0.15 g | 0.5–1.5 |
| Family car, 0–60 mph in 9 s (average) | 0.30 g | 3.0 |
| Hard braking in a normal car | 0.7–0.9 g | 7–9 |
| Fast electric car, 0–60 mph in 2.5 s (average) | 1.09 g | 10.7 |
| Large roller coaster at the bottom of a drop | 3–5 g | 30–50 |
| Free fall near Earth's surface | 1 g | 9.81 |
| Gravity on the Moon | 0.165 g | 1.62 |
Tips
- Average vs. peak: a 0–60 time gives the average acceleration. The push you feel at launch is usually stronger, and it tapers off as speed rises.
- Units with two time terms: km/h/s and mph/s mix hours and seconds. They are handy for vehicles but must be converted before using physics formulas such as F = m × a.
- Deceleration is just negative acceleration. Enter a negative value to convert braking figures; the sign carries through every unit.
Frequently asked questions
How do you convert m/s² to g?
Divide by 9.80665, the standard acceleration of gravity. For example, 19.6 m/s² ÷ 9.80665 = 2.0 g.
How many ft/s² is 1 g?
One standard g equals 32.174 ft/s² (9.80665 m/s² ÷ 0.3048 m per foot).
What is a Gal in acceleration?
The gal (Gal), named after Galileo, is a CGS unit equal to 1 centimeter per second squared, or 0.01 m/s². Geophysicists use the milligal (0.00001 m/s²) to measure tiny variations in Earth's gravity, and earthquake engineers sometimes quote ground acceleration in gals.
How many g is a 0–60 mph time of 3 seconds?
60 mph is 26.82 m/s, so 26.82 ÷ 3 = 8.94 m/s², which is about 0.91 g on average. A 6-second run averages about 0.46 g.
What does km/h/s mean?
Kilometers per hour per second is how much speed (in km/h) is gained each second. 1 km/h/s equals 0.2778 m/s². Car and train specs often use it because it relates directly to the speedometer.
Is g-force the same as acceleration?
G-force is acceleration expressed as a multiple of standard gravity (9.80665 m/s²). It is a convenient way to describe how strongly you are pushed into your seat, but it is not a force unit despite the name.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.