Acceleration Units Converter

Convert Acceleration Between Units

Acceleration Units Formula

Formula

\[a_{\text{to}}=a_{\text{from}}\times\frac{f_{\text{from}}}{f_{\text{to}}}\]

Where:

\(a_{\text{from}}\) — acceleration value entered in the From unit.
\(a_{\text{to}}\) — equivalent acceleration in the To unit.
\(f_{\text{from}}\) and \(f_{\text{to}}\) — the number of m/s² in one of each selected unit. The factors are 1 for m/s², 0.3048 for ft/s², 9.80665 for g, and 0.01 for Gal.

The calculator first expresses the entered value in m/s², then divides by the factor for the requested unit. This changes the unit without changing the physical acceleration.

Acceleration Units – Calculation Example

Example: convert the default value of 9.81 m/s² to g (gravity).

\[a_{\text{to}}=9.81\times\frac{1}{9.80665}=1.0003416\ldots\,g\]

Result: 1.000342 g, rounded to the six decimal places shown by the calculator.

How to use the calculator

Enter a nonnegative number in Acceleration value. Use the unit you plan to select in the next field; the number has no unit on its own.
Choose its current unit under From unit: m/s², ft/s², g (gravity), or Gal (Galileo).
Choose the unit you want under To unit. You can select the same unit to leave the value unchanged.
Read Converted Acceleration. The result includes the selected unit and is rounded to six decimal places.

For example, to express an acceleration reported in feet per second squared as a multiple of standard gravity, select ft/s² as the From unit and g (gravity) as the To unit. You do not need to convert through m/s² yourself.

What acceleration units mean

Acceleration describes how quickly velocity changes with time. An acceleration of 1 m/s² means the velocity changes by 1 meter per second in each second, assuming the acceleration stays constant. The unit ft/s² describes the same kind of quantity using feet instead of meters. Because one foot is exactly 0.3048 meters, 1 ft/s² equals exactly 0.3048 m/s².

The unit g expresses acceleration relative to standard gravity, defined as 9.80665 m/s². Thus, 1 g is an acceleration of 9.80665 m/s², while 2 g is twice that value. It is a reference unit, not a claim that the local gravitational acceleration is identical everywhere. In the default example, 9.81 m/s² is slightly greater than 1 g because 9.81 is slightly greater than 9.80665.

Gal, named for Galileo, is a smaller acceleration unit: 1 Gal equals 1 centimeter per second squared, or 0.01 m/s². It can be useful when acceleration differences are small, including in some measurements of gravity. For scale, standard gravity equals 980.665 Gal. The calculator uses Gal as the unit symbol; it does not offer inches per second squared or any units beyond the four listed in its menus.

A conversion preserves the size of a physical acceleration; it does not calculate acceleration from distance, time, or force. If you are working from mass and acceleration to find a force, use a force converter for the resulting force units. Torque and pressure also have their own units and cannot be obtained by simply changing an acceleration unit.

Assumptions and practical tips

Use a nonnegative magnitude. The Acceleration value field has a minimum of zero. If direction matters, keep track of it separately; this converter does not represent signed components or vectors.
Check what “g” means in your source. Here it always means standard gravity, 9.80665 m/s², not a location-specific measurement of Earth’s gravity.
Keep rounding in mind. The displayed result is rounded to six decimal places. A very small nonzero conversion may therefore appear as zero, and converting a rounded result back may not reproduce every digit of the original value.
Match the source unit before interpreting the answer. Entering 9.81 with g selected under From unit means 9.81 g, not 9.81 m/s². That difference is nearly a factor of ten.

Frequently Asked Questions

How can I convert ft/s² to Gal by hand?

Multiply the value in ft/s² by 30.48. A foot contains exactly 30.48 centimeters, and a Gal is one centimeter per second squared. For example, \(3\,\text{ft/s}^2 = 91.44\,\text{Gal}\). To go the other way, divide the value in Gal by 30.48.

What is a typical acceleration for a car?

A car accelerating from rest might average roughly 2–5 m/s², depending on the vehicle, road conditions, and how it is driven. That is about 0.2–0.5 g. Acceleration is not usually constant throughout a trip, so a single figure is best treated as an average over a specified time interval, not a universal “normal” value.

How do I convert mph per second or km/h per second to m/s²?

Multiply mph per second by 0.44704 to get m/s². For km/h per second, divide by 3.6. For example, an increase of 10 mph each second is \(4.4704\,\text{m/s}^2\). These units describe a change in speed each second; an ordinary speed in mph or km/h cannot be converted to acceleration without knowing how quickly it changes.

Is acceleration in g the same as the g-force a person feels?

Not necessarily. The unit g compares an acceleration with standard gravity, while the force a person feels depends on how their body is supported and how the acceleration acts on it. For example, an accelerometer at rest on Earth can read about 1 g, while one in free fall reads near zero. Duration and direction also matter when discussing effects on people.

Can an object have zero acceleration while it is moving?

Yes. An object moving in a straight line at constant velocity has zero acceleration, even if it is moving quickly. Acceleration occurs when velocity changes in magnitude or direction. That is why an object traveling around a curve can have nonzero acceleration even when its speed stays constant.

Can I convert an acceleration value directly into a force?

No. Acceleration and force measure different quantities; changing acceleration units does not supply a force value. To find net force in newtons, you also need the object's mass in kilograms and can use \(F=ma\), with acceleration in m/s². The calculation assumes the mass and acceleration refer to the same object and that the acceleration is its net acceleration.