Acceleration Converter
Convert between m/s², g-force, and ft/s² acceleration units
About This Tool
Acceleration is the rate of change of velocity, with SI unit m/s². g-force expresses it as a multiple of standard gravity, where 1g = 9.80665 m/s². ft/s² is the imperial counterpart used in US engineering.
This converter handles the three units bidirectionally with full precision. Useful for physics homework, automotive specs, and aerospace conversions where mixed-unit literature is the norm.
The constant 9.80665 m/s² is the standard gravity defined by the 3rd CGPM in 1901 and codified in ISO 80000-3. It's a reference value, not a measurement — actual gravitational acceleration at the Earth's surface varies between roughly 9.78 m/s² at the equator and 9.83 m/s² at the poles, plus altitude effects of about −0.003 m/s² per kilometer of elevation. Aerospace engineering and physics coursework treat 9.80665 as exact; precision metrology uses local gravity. The ft/s² unit derives directly from the foot definition (0.3048 m exactly), making 1 g = 32.17405 ft/s².
A worked example: a Tesla Model S Plaid with a quoted 0–60 mph time of 1.99 seconds. Converting 60 mph to 26.82 m/s and dividing by 1.99 s gives an average acceleration of 13.48 m/s², which is 1.375 g or 44.21 ft/s². Peak acceleration during launch is higher — published g figures from manufacturers are typically the time-averaged value, since peak is briefly limited by tire grip at the moment of takeoff. A Formula 1 car under heavy braking can hit 5 g sustained, far above any production road car.
Limitations: the converter handles unit conversion only, not vector mathematics. Acceleration in the real world has direction; a car decelerating at 1 g in the longitudinal direction and zero laterally is a different event from 1 g of cornering force. Convert magnitudes here and handle direction separately. The converter also doesn't account for centrifugal or Coriolis pseudoforces in rotating reference frames — those require explicit treatment. For relativistic regimes (acceleration approaching c per second of proper time), Newtonian conversion stops being meaningful.
The about text and FAQ on this page were drafted with AI assistance and reviewed by a member of the Coherence Daddy team before publishing. See our Content Policy for editorial standards.