Calculate Acceleration, Velocity, Time

Calculator, how long it takes with which acceleration to reach a certain speed. If you enter two values, the third value will be calculated. The time can be specified in days (d), hours (h), minutes (m) and seconds (s). The units for speed are kilometers per hour (km/h), meters per second (m/s), miles per hour (mph), or the speed of light (c). Acceleration is given in meters per square second (m/s²) or as a multiple of the gravitational acceleration (g). It is not possible to reach or exceed the speed of light, even if values greater than 1 c can be calculated here.

Time t:	d, h, m, s
Velocity v:
Acceleration a:

a = v / t, 1 c = 299792458 m/s, 1 g = 9.81 m/s².

Example: an (unmanned) spaceship that should accelerate to 90% the speed of light (0.9 c) would need more than 63½ days at a constant acceleration of 5 g.

Physics commonly uses SI units. Here is a calculator to convert units.