Physics

Spring Force Constant Calculator

Spring force and stored energy from Hooke's law.

Enter your values

Enter the spring constant in N/m.

Enter the displacement in m.

Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.

Results
Restoring force
20 N
Stored elastic energy
0.8 J
Spring constant
250 N/m

Quick answer

Force F = k x x, and stored energy U = 0.5 x k x x^2.

F = kx, U = 0.5 k x^2

At a glance

What it doesSpring force and stored energy from Hooke's law.
CategoryPhysics
Inputs neededSpring constant, Displacement
Main outputRestoring force
FormulaF = kx, U = 0.5 k x^2
CostFree — no sign-up, no download

How to use the Spring Force Constant Calculator

  1. 1Enter the spring constant, found from force divided by extension.
  2. 2Enter the displacement from the spring's natural length.
  3. 3Read the restoring force and the energy stored in the spring.

Inputs explained

Spring constant(N/m)
Enter the spring constant in N/m.
Displacement(m)
Enter the displacement in m.

Worked example

Using the values the calculator loads with:

Inputs

  • Spring constant250 N/m
  • Displacement0.08 m

Results

  • Restoring force20 N
  • Stored elastic energy0.8 J
  • Spring constant250 N/m

Frequently asked questions

What if the spring is compressed instead of stretched?

Hooke's law works the same way; just use a negative displacement, force will act outward.

Is this valid for large stretches?

Hooke's law only holds within the spring's elastic limit.

What do I need to enter into the Spring Force Constant Calculator?

Just 2 values: spring constant, displacement. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.

How does the Spring Force Constant Calculator work out the answer?

Force F = k x x, and stored energy U = 0.5 x k x x^2. It applies the formula F = kx, U = 0.5 k x^2 and shows the working so you can check each step by hand.

Is the Spring Force Constant Calculator free, and do I need an account?

It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.