Scientific Converters Precise unit conversions for science & engineering.

    Loading…

    Hooke's Law Calculator

    A 200 N/m spring stretched 0.25 m pulls back with 50 N (F = kx) and stores 6.25 J of elastic energy.

    Solve for:
    Spring force F =

    50 N

    In kN
    0.05 kN
    In mN
    50000 mN
    In lbf
    11.24044715 lbf
    In kgf
    5.098581065 kgf
    In dyn
    5000000 dyn
    Elastic potential energy ½kx²
    6.25 J
    Step-by-step solution
    1. F = k × x
    2. F = 200 × 0.25
    3. F = 50 N

    Hooke's Law Formula

    F = k x

    F spring force, k spring constant (stiffness), x extension or compression; energy E = ½kx²

    Worked Example

    A spring with k = 200 N/m stretched 0.25 m:

    1. F = k × x
    2. F = 200 × 0.25
    3. F = 50 N

    In mN: 50000 mN · In lbf: 11.24044715 lbf · In kgf: 5.098581065 kgf · In dyn: 5000000 dyn · Elastic potential energy ½kx²: 6.25 J

    Springs in series and parallel

    Two springs side by side (parallel) add: k = k₁ + k₂. End to end (series) they combine like resistors in parallel: 1/k = 1/k₁ + 1/k₂, so the pair is softer than either spring.

    More Forces and Newton’s Laws Calculators

    Frequently asked questions

    How do I find the spring constant from a graph?

    Plot force against extension; the slope of the straight part is k. Beyond the elastic limit the line curves and Hooke’s law no longer applies.

    Why is there a minus sign in some books?

    F = −kx states that the restoring force opposes the displacement. The calculator works with magnitudes.

    Sources

    Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.

    Cite this page

    APA

    Scientific Converters. (2026, October 15). Hooke's Law Calculator. Retrieved October 25, 2026, from https://scientificconverters.com/calculators/hookes-law-calculator/

    IEEE

    Scientific Converters, "Hooke's Law Calculator," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/calculators/hookes-law-calculator/

    Send feedback

    Found a wrong value, a missing unit or an idea? Tell us. We read every message.

    What is it about?

    We store your message, the page you were on and your email if given. See the privacy policy.