Linear Acceleration Converter
Convert linear acceleration between m/s², cm/s², ft/s², in/s², Gal, and standard gravity (g). Enter a value, then choose the units to convert from and to.
Convert Linear Acceleration Between Units
Linear Acceleration Formula
Where:
- \(a_{\mathrm{from}}\) — the acceleration value entered in the From unit
- \(a_{\mathrm{to}}\) — the converted value in the To unit
- \(f_{\mathrm{from}}\) — the number of m/s² in one From unit
- \(f_{\mathrm{to}}\) — the number of m/s² in one To unit
The converter first expresses the entered acceleration in m/s², then divides by the factor for the selected output unit. The factors are listed below.
Linear Acceleration – Calculation Example
Example: convert the default value of 9.81 m/s² to standard gravity (g). One g is exactly 9.80665 m/s².
\[9.81\,\mathrm{m/s^2}\times\frac{1}{9.80665}\approx 1.000342\,g\]
Result: 9.81 m/s² is approximately 1.000342 g, as displayed to six decimal places.
How to use the calculator
- Enter a nonnegative number in Acceleration value. The default is 9.81.
- Choose the unit of that number in From unit. The default is meters per second squared (m/s²).
- Choose the unit you want in To unit. The default is standard gravity (g).
- Read Converted Acceleration. The result includes the selected output unit and is rounded to six decimal places.
You can select the same unit in both menus to leave the numerical value unchanged. To reverse a conversion, swap the From unit and To unit and enter the value you want to convert back.
What linear acceleration means
Linear acceleration describes how quickly an object's velocity changes over time. An acceleration of 1 m/s² means its velocity changes by 1 m/s each second. Acceleration can describe speeding up, slowing down, or a change in direction; although “linear” distinguishes this quantity from angular acceleration, velocity and acceleration are vector quantities and need not point along the same line.
This calculator converts the magnitude of an acceleration between units. It does not determine acceleration from distance and time, calculate a direction, or predict motion. For example, an acceleration stated as 981 Gal and the same acceleration stated as 9.81 m/s² describe equal magnitudes. Changing units does not change the physical motion.
Standard gravity, written g, provides a convenient reference for acceleration measurements in transportation, device sensors, and engineering. It is a defined unit equal to exactly 9.80665 m/s², not a measurement of gravity at a particular location. Thus 1 g is approximately 32.174 ft/s². If you also need to relate acceleration to an object's mass, use the Force converter to express the resulting force in appropriate units. For rotational quantities rather than linear motion, the Moment of Inertia converter covers a different kind of measurement.
Unit factors used by the converter
Each factor below is the number of meters per second squared in one unit. To convert manually, multiply your value by the From unit's factor and divide by the To unit's factor.
| Unit | Symbol | Factor in m/s² |
|---|---|---|
| Meter per second squared | m/s² | 1 |
| Centimeter per second squared | cm/s² | 0.01 |
| Foot per second squared | ft/s² | 0.3048 |
| Inch per second squared | in/s² | 0.0254 |
| Galileo | Gal | 0.01 |
| Standard gravity | g | 9.80665 |
A Gal is exactly 1 cm/s², so those two choices always produce the same numerical value when converting from the same input. Gal is commonly used for gravitational acceleration in geophysics; centimeters per second squared can be useful wherever smaller SI-based units are preferred.
Assumptions and practical limits
The Acceleration value field accepts zero or positive numbers. If you are working with signed acceleration along an axis, convert its magnitude here and apply the sign separately. A negative sign can indicate direction or deceleration under a chosen coordinate convention; it is not a different unit.
Results are rounded to six decimal places for display. Very small nonzero conversions may therefore appear as zero, and converting a displayed rounded result back may not reproduce the original value exactly. Keep extra digits during intermediate calculations when precision matters. The unit factors for feet, inches, standard gravity, and Gal are defined values; any difference between a calculated value and the displayed result comes from rounding, not a change in the underlying unit definitions.
Frequently Asked Questions
How do I calculate acceleration from two speed readings?
Divide the change in velocity by the elapsed time: \(a_{\mathrm{avg}}=(v_2-v_1)/\Delta t\). If a vehicle goes from 0 to 20 m/s in 5 seconds, its average acceleration is 4 m/s². This does not mean it accelerated at exactly 4 m/s² throughout the interval.
What is a normal acceleration for a car?
There is no single normal value; it depends on the vehicle and how it is driven. A car reaching 60 mph from rest in 10 seconds has an average acceleration of about 2.68 m/s², or 0.27 g. Its acceleration at any particular moment may be higher or lower.
How do I convert mph per second or km/h per second to m/s²?
Convert the speed change to meters per second, while leaving the time interval in seconds. Multiply mph per second by 0.44704, or divide km/h per second by 3.6. For example, a speed increase of 10 km/h each second is an acceleration of about 2.78 m/s². You can then enter that value in the converter.
Why does my phone accelerometer show about 1 g when the phone is still?
An accelerometer senses the supporting force that prevents it from falling, so a stationary phone typically reports a total magnitude near 1 g. In free fall, it would read close to 0 g even while gaining speed. Individual axis readings depend on the phone’s orientation; some apps also process sensor data to estimate motion acceleration.
Are g and g-force the same as force?
No. A reading in g expresses acceleration relative to standard gravity; it is not a force unit such as the newton. “G-force” is an informal way to describe the loading associated with acceleration. The force involved depends on mass and the situation, so you cannot convert a g reading directly into newtons without more information.
Can an object accelerate while moving at a constant speed?
Yes. Acceleration also occurs when velocity changes direction. An object moving in a circle at constant speed has centripetal acceleration of magnitude \(a=v^2/r\), directed toward the center. At 10 m/s around a circle of radius 20 m, that magnitude is 5 m/s². The converter can change its units, but it does not calculate the direction.