Physics calculators
6 free tools
The equations from first-year physics, ready to run — velocity, force, density, energy, and a bit of circuit theory. Type in what you know and the calculator rearranges the formula for you.
Average speed from a distance and a time, in m/s and km/h.
Newton's second law, F = ma — solve for force, mass, or acceleration.
Density, mass, or volume from the other two using ρ = m/V.
The energy of a moving object from its mass and velocity, KE = ½mv².
Enter any two of voltage, current, and resistance to get the rest, plus power.
Work from force and distance, and power once you add a time.
Frequently asked questions
Which physics calculator should I start with?
Follow the quantity you're chasing. Chasing a speed? The Velocity Calculator. Sorting out a push or pull? The Force Calculator. Working with electricity? Ohm's Law. Each one takes a couple of numbers and hands back the rest.
What units do these calculators use?
SI units throughout — meters, seconds, kilograms, newtons, joules, watts, volts, amps, and ohms. Stick to those and the results come out in the standard units physicists and textbooks use.
Are the results exact?
The math is exact for the idealized formulas. Real experiments bring in friction, air resistance, heat loss, and measurement error, so treat these as clean textbook answers rather than lab-grade predictions.
Which of these tools pair up well?
A few natural combos: Velocity feeds straight into Kinetic Energy, Force sits next to Work & Power, and Ohm's Law rounds out the electrical side. Run them together when a problem spans more than one formula.