Acceleration Converter

1. Enter the value you want to convert.
2. Choose the from unit.
3. Choose the to unit.
4. Read the result, plus m/s2 and g-force.

Here is what each result means:

Acceleration is the rate at which speed changes. A car pulling away, a lift starting to rise and a falling object all accelerate. Because it is a change in speed over time, its units combine a speed unit with a time unit, and several combinations are in common use across science, motoring and engineering.

The SI unit is metres per second squared, the change of one metre per second in speed each second. A very useful reference is standard gravity, written g, which is 9.80665 metres per second squared, the acceleration of a freely falling object near the Earth's surface. Expressing an acceleration in g makes it easy to picture, since 1 g is the familiar pull of gravity.

This converter bridges every unit through metres per second squared. It multiplies your value by the metres per second squared in its unit, then divides by the value in the target unit. Because each unit has a fixed value, the conversions are exact and never change.

Motoring often describes acceleration as a change of speed per second, such as kilometres per hour per second or miles per hour per second. These are handy for everyday driving, since they say directly how quickly a car gains speed, and the converter turns them into the scientific units and back.

It converts through metres per second squared, the SI unit.

1. Your value is multiplied by its unit's value in metres per second squared.
2. That gives the acceleration in metres per second squared, the common base.
3. Dividing by the target unit's value gives the result.

For the physics of motion, see the acceleration calculator and the velocity calculator.

Convert 1 g to metres per second squared.

Result: 1 g is 9.80665 m/s2, the acceleration of gravity near the Earth's surface. That is about 32.17 feet per second squared, or 35.3 kilometres per hour per second.

Every unit has a fixed value in metres per second squared.

The gal, or centimetre per second squared, is used in gravimetry and seismology for small accelerations. Standard gravity is the anchor that links everyday g-force to the scientific units.

Each unit suits a different way of thinking about acceleration.

Scientists use metres per second squared, while drivers think in terms of how much speed is gained each second. Expressing an acceleration in g makes extreme values easy to grasp: a few g is a hard brake, and several g is what fighter pilots feel.

The Two Units

The ratio between the from-unit and to-unit sets the result; each has a fixed value in m/s2.

The Value of G

Standard gravity is fixed at 9.80665, though local gravity varies slightly across the Earth.

The Speed and Time Units

Speed-per-second units like km/h/s mix a speed unit with a per-second rate.

Physics and Engineering

Switch between m/s2 and other units in calculations.

Motoring

Turn a car's speed gain per second into g-force or m/s2.

Everyday Comparison

Express an acceleration in g to compare it with gravity.

1. Forgetting G Is 9.81

One g is 9.80665 m/s2, not 1. Treating g as 1 is a large error.

2. Mixing Speed and Time Units

Km/h/s and mph/s mix a speed unit with a per-second rate. Keep them straight.

3. Confusing Acceleration and Speed

Acceleration is how fast speed changes, not the speed itself.

4. Wrong Direction

Check which unit is the from and which is the to; swapping them inverts the result.

5. Using Local Gravity

The converter uses standard gravity. Local gravity differs by a fraction of a percent.

Conversions use fixed factors relative to metres per second squared.

9.80665 m/s2. That is standard gravity, the acceleration of a freely falling object near the Earth's surface.

Divide by 9.80665. So 19.6 m/s2 is about 2 g. To go the other way, multiply g by 9.80665.

G-force expresses acceleration as a multiple of standard gravity. One g is the pull of gravity; a few g is felt as a hard push in a fast turn or a hard brake.

Multiply feet per second squared by 0.3048. So 32.17 ft/s2, which is 1 g, is about 9.81 m/s2.

Kilometres per hour per second, the change in speed of one kilometre per hour each second. It is a handy way to describe how fast a car speeds up.

The metre per second squared. It means the speed changes by one metre per second every second.

Standard gravity is fixed at 9.80665 m/s2. Actual local gravity varies by a fraction of a percent with latitude and altitude.

A gal is a centimetre per second squared, used in gravimetry and seismology for small accelerations. It is one hundredth of a metre per second squared.

No. The calculation runs in your browser and nothing you enter is stored or sent anywhere, unless you choose Save, which keeps the result only on this device.

• Acceleration (Wikipedia).
• Standard gravity (Wikipedia).
• g-force (Wikipedia).