Physics Tools

Force Calculator

Enter mass and acceleration to calculate ideal net force, then use the connected workflow when the problem changes from translation to energy, impulse, or rotation.

Mass

Acceleration (m/s²)

—N

—kN

—lbf

—acceleration / g

—Net force F = ma

These are idealized classical-physics calculations. Real systems can differ because of air resistance, friction, deformation, measurement uncertainty, non-constant forces, or other effects not included in the selected model.

Solve force, mass, or acceleration

Use Newton's second law in either direction and keep unit conversions visible in the same result.

Solve forForce (N)Mass (kg)Acceleration (m/s²)

—Requested result

—Force (lbf)

—Acceleration (g)

F = m × a

Constant-mass classical model. Enter net acceleration; friction, drag and other forces must already be represented in the acceleration or force balance.

State the model before trusting the number

Classical formulas are only as good as their assumptions and units. Air resistance, damping, deformation, non-constant forces and measurement uncertainty are not silently invented when the selected model does not include them.

Governing physics model

F = ma — constant-mass Newtonian translation.

How to verify the result

Divide the reported net force by mass: it should return the entered acceleration. Reversing acceleration should reverse force sign.

Domain and assumption boundary

Mass is non-negative. Acceleration and net force may be signed along the chosen axis. The calculator does not silently add drag, damping, deformation, varying fields, relativistic effects, measurement uncertainty, or geometry that the selected model does not contain.