Spring Rate Calculator

Find a spring's rate from force and deflection.

Spring rate (N/mm) 5

Spring rate (N/m) 5,000

Formula: k = force ÷ deflection

Step-by-step with your numbers:

1. Values used:

2. Force = 200 N

3. Deflection = 40

5. Spring rate = Force / Deflection = 200 / 40 = 5N/mm

6. Spring rate = 5,000N/m

Did we solve your problem today?

Spring rate is how much force a spring needs per unit of compression.

The math behind it

k = force ÷ deflection (Hooke's law). A higher rate means a stiffer spring.

200 N compressing 40 mm → 5 N/mm.

Stiffer or softer for comfort?

Softer springs absorb bumps better but allow more body movement.