Acceleration Converter
Convert linear acceleration, the rate at which speed changes, between meters per second squared, standard gravity (g), feet per second squared, Gal and other units. Pick two units, enter a value and read the result instantly.
Select two units to see the conversion factor.
This tool converts linear acceleration (length per time squared) only. It is not angular acceleration (rad/s²), not velocity and not force. A value in “g” here means a multiple of standard gravity, 9.80665 m/s².
Acceleration Formula
Every acceleration unit is a fixed multiple of the meter per second squared. Result = value × (source factor ÷ target factor). The building blocks are exact: 1 ft = 0.3048 m, 1 in = 0.0254 m, 1 yd = 0.9144 m, 1 mi = 1,609.344 m, 1 Gal = 1 cm/s² = 0.01 m/s², and standard gravity g = 9.80665 m/s² by definition.
What Is Acceleration?
Linear acceleration is the rate at which the velocity of an object changes along a straight or curved path: a = Δv ÷ Δt. The SI unit is the meter per second squared (m/s²). An acceleration of 1 m/s² means the speed changes by 1 m/s every second. Slowing down is acceleration too, with the opposite sign, which is why this converter accepts negative values.
Several unit families are in everyday use. Engineers and physicists use m/s² and its prefixed forms. Imperial and US customary work uses ft/s², in/s², yd/s² and mi/s². Vehicle, aerospace and human-factors work often expresses acceleration as a multiple of standard gravity (g), exactly 9.80665 m/s². Geophysics and gravimetry use the gal (also written galileo, Gal), equal to 1 cm/s² or 0.01 m/s². The gal and the galileo are the same unit and both are listed.
Do not confuse linear acceleration with related quantities. It is not angular acceleration (rad/s²), which describes how quickly rotation speeds up (Acceleration - Angular Converter). Rotation and straight-line motion are linked by a = α × r, but only with α in rad/s². Acceleration is also not velocity or speed (mph to kph converts speed), and it is not force: force equals mass times acceleration.
Supported Units
This converter supports the following 19 acceleration units. The last column gives the value of each unit in the base unit, the meter per second squared. “Standard gravity” is the conventional value 9.80665 m/s², not the local gravity at a particular place, which varies slightly with latitude and altitude.
| Unit | Symbol | Value in m/s² |
|---|---|---|
| Meter per second squared | m/s² | 1 |
| Acceleration of gravity (standard gravity) | g | 9.80665 |
| Centimeter per second squared | cm/s² | 0.01 |
| Foot per second squared | ft/s² | 0.3048 |
| Inch per second squared | in/s² | 0.0254 |
| Yard per second squared | yd/s² | 0.9144 |
| Mile per second squared | mi/s² | 1,609.344 |
| Gal | Gal | 0.01 |
| Galileo | Gal | 0.01 |
| Kilometer per second squared | km/s² | 1,000 |
| Hectometer per second squared | hm/s² | 100 |
| Dekameter per second squared | dam/s² | 10 |
| Decimeter per second squared | dm/s² | 0.1 |
| Millimeter per second squared | mm/s² | 0.001 |
| Micrometer per second squared | µm/s² | 1e-6 |
| Nanometer per second squared | nm/s² | 1e-9 |
| Picometer per second squared | pm/s² | 1e-12 |
| Femtometer per second squared | fm/s² | 1e-15 |
| Attometer per second squared | am/s² | 1e-18 |
How to Use the Acceleration Converter
- Type the acceleration in the value box. Decimals and scientific notation such as 0.0025 or 2.5e-3 are accepted.
- Choose the From unit and the To unit.
- The result appears instantly, or press Convert Now. Very large or very small results are shown in scientific notation.
- Use Swap Units to reverse the conversion, Copy Result to copy the answer, open Show this value in all units for a full list, and Clear to start again.
Step-by-step by hand
- Find the size of each unit in the common base unit (m/s²): 1 g = 9.80665 m/s² and 1 ft/s² = 0.3048 m/s².
- Divide the source size by the target size to get the conversion factor: 9.80665 ÷ 0.3048 = 32.17404856, so 1 g = 32.17404856 ft/s².
- Multiply by your value: 1 g × 32.17404856 = 32.17404856 ft/s².
Acceleration can be positive or negative (a negative value means slowing down or acceleration in the opposite direction), so a minus sign is accepted. Zero is also valid.
Common Acceleration Conversions
- Standard gravity: 1 g equals 9.80665 m/s², 32.17404856 ft/s² and 980.665 Gal.
- Roller coaster or aircraft manoeuvre: 5 g equals 49.03325 m/s².
- Hard braking: 8 m/s² equals 0.8157729704 g and 26.24671916 ft/s².
- Imperial to metric: 32.174 ft/s² equals 9.8066352 m/s².
- Geophysics: 980.665 Gal equals 9.80665 m/s².
- Small units: 2.5 cm/s² equals 0.025 m/s² and 0.9842519685 in/s².
Standard Gravity (g) to Other Acceleration Units
Quick reference for frequently used values
| g | m/s² | ft/s² | Gal |
|---|---|---|---|
| 0.1 | 0.980665 | 3.217404856 | 98.0665 |
| 0.25 | 2.4516625 | 8.043512139 | 245.16625 |
| 0.5 | 4.903325 | 16.08702428 | 490.3325 |
| 1 | 9.80665 | 32.17404856 | 980.665 |
| 2 | 19.6133 | 64.34809711 | 1,961.33 |
| 5 | 49.03325 | 160.8702428 | 4,903.325 |
| 9 | 88.25985 | 289.566437 | 8,825.985 |
| 10 | 98.0665 | 321.7404856 | 9,806.65 |
Where and Why This Conversion Is Used
- Automotive and rail: braking, launch and cornering performance, passenger comfort limits.
- Aerospace and human factors: g-loads on pilots, astronauts and equipment, launch and re-entry profiles.
- Structural and vibration engineering: shock and vibration specifications, seismic ground acceleration, accelerometer data.
- Physics and education: moving between SI and imperial values for free-fall and projectile problems.
- Geophysics: gravity surveys and tidal gravity measurements in gal.
Limitations
- The converter changes units only. To get a force, multiply the acceleration in m/s² by a mass in kg to get newtons.
- “g” means exactly 9.80665 m/s² here, even though real gravity at a given location differs slightly.
Important Differences Between Related Measurements
- Linear acceleration vs angular acceleration: linear acceleration is length per time squared (m/s²). Angular acceleration is angle per time squared (rad/s²). A point at radius r on a rotating body has a tangential acceleration a = α × r.
- Acceleration vs velocity: velocity is how fast and in which direction something moves. Acceleration is how quickly that velocity changes. A car cruising at constant speed in a straight line has zero acceleration.
- Acceleration vs force: force is mass times acceleration (F = m × a). The same acceleration needs a larger force for a larger mass.
- “g” as a unit vs gravity itself: expressing an acceleration “in g” compares it with standard gravity. It does not mean gravity is acting. The gal (cm/s²) is a different, smaller unit that is also used for gravity measurements.
Each converter on this site changes units within one quantity only, and none of them mixes quantities. The related tools are: Velocity - Angular, Acceleration, Acceleration - Angular, Density, Specific Volume, Moment of Inertia, Moment of Force and Torque.