Engineering converters
Acceleration Converter
Convert m/s², ft/s², g-force, gal and other acceleration units.
Result
9.80665 m/s²
1 g = 9.80665 m/s²
All units for this value
| Unit | Symbol | Value |
|---|---|---|
| Meter per second squared | m/s² | 9.80665 |
| Decimeter per second squared | dm/s² | 98.0665 |
| Centimeter per second squared | cm/s² | 980.665 |
| Millimeter per second squared | mm/s² | 9806.65 |
| Kilometer per second squared | km/s² | 0.00980665 |
| Galileo (gal) | Gal | 980.665 |
| Kilometer per hour per second | km/h/s | 35.3039 |
| Mile per hour per second | mph/s | 21.9369 |
| Knot per second | kn/s | 19.0626 |
| Inch per second squared | in/s² | 386.089 |
| Foot per second squared | ft/s² | 32.174 |
| Mile per second squared | mi/s² | 0.00609357 |
| Standard gravity (g) | g | 1 |
About this calculator
Acceleration measures how quickly velocity changes over time, expressed as a speed unit per unit of time. This converter switches between metric units like metres per second squared, imperial units like feet per second squared, and gravity-based units like standard g, useful for vehicle testing, physics problems, and engineering specifications.
How it works in plain English
Every acceleration unit here can be expressed as a multiple of metres per second squared, the SI base unit, so the converter uses it as a common anchor. Your entered value is multiplied by a fixed factor to reach that anchor, then divided by the target unit's factor to produce the final result. This two-step process keeps every conversion pair consistent, whether you're moving between metric prefixes, imperial units, or gravity-based measures.
Standard gravity, written as g, is a defined constant equal to 9.80665 m/s², representing the acceleration a falling object experiences near Earth's surface. It's widely used to describe forces felt during vehicle acceleration, roller coasters, and aerospace maneuvers, since expressing acceleration as a multiple of g gives an intuitive sense of felt force. The galileo (Gal), a CGS unit equal to one centimetre per second squared, appears in geophysics and gravimetry.
Pick your source and target units from the from and to menus, enter a number, and the result updates instantly. A complete table shows that same acceleration expressed in every supported unit at once, a precision control adjusts the number of decimal places shown, and a swap button flips the two chosen units with a single click.
The formula
- value_in_target = value_in_source × (source factor to m/s²) ÷ (target factor to m/s²)
- 1 g = 9.80665 m/s²
- 1 ft/s² = 0.3048 m/s²
- 1 Gal = 0.01 m/s²
- 1 km/h/s = 1 ÷ 3.6 m/s²
- 1 mph/s = 0.44704 m/s²
Worked example
Suppose a sports car's spec sheet claims a 0-100 km/h test that averages 1.2 g and you want that figure in metres per second squared to compare it against a textbook formula. Multiply by the defined gravity constant: 1.2 g × 9.80665 m/s² = 11.7680 m/s². This single multiplication converts the gravity-based reading directly into the SI unit.
Entering 1.2 into the g field with m/s² selected as the target shows 11.7680 m/s² immediately. As a sanity check, that figure is a little over ten times normal gravity, which is roughly what a very quick launch feels like, so the size of the answer looks reasonable rather than being off by an order of magnitude. The full unit table displayed at the same time also confirms this equals about 38.61 ft/s² and roughly 42.36 km/h per second, all calculated from the same entered value without any further typing.
Common acceleration unit equivalents
| Unit | Equal to (m/s²) |
|---|---|
| 1 m/s² | 1 |
| 1 cm/s² | 0.01 |
| 1 km/s² | 1000 |
| 1 Gal | 0.01 |
| 1 ft/s² | 0.3048 |
| 1 in/s² | 0.0254 |
| 1 mi/s² | 1609.344 |
| 1 km/h/s | 0.277778 |
| 1 mph/s | 0.44704 |
| 1 g (standard gravity) | 9.80665 |
Standard unit definitions
Frequently asked questions
What exactly is 'g' and why is it so precise a number?
Standard gravity (g) is a fixed, internationally defined constant equal to exactly 9.80665 m/s², representing a conventional average of Earth's gravitational acceleration at sea level. It's not the exact gravity felt everywhere on Earth, since local gravity varies slightly with latitude and altitude, but it serves as a universal reference for comparing forces.
How is g-force different from actual acceleration in m/s²?
They describe the same physical quantity, acceleration, just on different scales. Expressing a value in g tells you how many multiples of Earth's standard gravitational acceleration it represents, which is intuitive for describing felt forces during braking, cornering, or aerospace maneuvers, while m/s² is the direct SI measurement used in most physics calculations.
What is a galileo (Gal) used for?
The galileo is a CGS unit equal to one centimetre per second squared, or 0.01 m/s². It's primarily used in geophysics and gravimetry to measure small variations in Earth's gravitational field, since those variations are typically far smaller than one full metre per second squared.
Can I convert acceleration units that mix speed and time bases, like mph per second?
Yes. Units like km/h/s and mph/s describe how quickly a speed measured in those units changes each second, and the converter handles them the same way as any other acceleration unit by converting through the common metres-per-second-squared anchor, so no manual unit juggling is required.
How precise are the converted results?
Conversions use exact defined factors, such as 9.80665 for standard gravity and 0.3048 for feet, so results are as accurate as the number of decimal places you choose to display. The precision control lets you widen or narrow that display, which is useful when comparing closely matched acceleration values.
Related converters
Convert rpm, radians per second, degrees per second and revolutions per hour.
Convert rad/s², degrees per second squared and revolutions per minute squared.
Convert kg/m³, g/cm³, lb/ft³, lb/gal and other density units.
Convert m³/kg, ft³/lb and the reciprocal density units they invert to.