Acceleration Calculator

Average acceleration equals the change in velocity divided by elapsed time: a = (v - u) / t, where u is the initial velocity, v is the final velocity, and t is the time in seconds. The result is in meters per second squared (m/s^2). For example, a car that goes from 0 to 27 m/s (roughly 60 mph) in 6 seconds accelerates at 4.5 m/s^2.

Switch to Newtonian mode and the calculator applies F = m * a. You can solve for any one of the three quantities: force (given mass and acceleration), mass (given force and acceleration), or acceleration (given force and mass). Mass must be positive, and the calculator rejects zero acceleration when solving for mass because dividing by zero is undefined.

One g is exactly 9.80665 m/s^2, the standard gravitational acceleration defined by the CGPM. G-units make the result tangible: a hard-braking car hits roughly 1 g, a roller coaster pulls 3-5 g through a loop, and a fighter jet pulling out of a dive can exceed 9 g. The calculator converts any computed acceleration to g automatically.

Yes. The sign describes direction along the chosen axis, not whether speed is increasing. An object slows when acceleration points opposite its velocity and speeds up when both have the same sign. A car moving in the positive direction and braking from 20 m/s to rest in 4 seconds has acceleration -5 m/s^2.

All inputs are in SI units: velocity in meters per second (m/s), time in seconds (s), mass in kilograms (kg), force in newtons (N), and acceleration in m/s^2. Results are shown in those same SI units plus convenient alternates: g-units for acceleration, pound-force (lbf) for force, and pounds (lb) for mass.