Spring Constant Calculator
Hooke's law force, extension and energy.
Enter your values
ⓘ Live results
Results
- Force
- 30 N
- Stored energy
- 1.8 J
- Extension under mass
- 0.1177 m
- Oscillation period
- 0.688 s
Quick answer
Hooke's law says force is proportional to extension for an ideal spring.
F = kx; E = ½kx²
How to use the Spring Constant Calculator
- 1Enter the spring constant in N/m.
- 2Enter the extension or compression.
- 3Add a mass to see static deflection and period.
Worked example
Using the values the calculator loads with:
Inputs
- Spring constant250 N/m
- Extension0.12 m
- Attached mass3 kg
Results
- Force30 N
- Stored energy1.8 J
- Extension under mass0.1177 m
- Oscillation period0.688 s
Frequently asked questions
Does Hooke's law always hold?
Only below the elastic limit — beyond it the spring deforms permanently.
How do I measure k?
Hang a known mass and divide its weight by the extension.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.