What Hooke’s Law describes
Hooke’s Law states that the force needed to stretch or compress a spring by some distance is proportional to that distance: F = kx, where k is the spring constant (stiffness) and x is the displacement from the spring’s natural length.
How this calculator works
Enter the spring constant and how far the spring is stretched or compressed. The calculator multiplies these together to give the magnitude of the spring force in newtons. In real springs the actual restoring force acts opposite to the displacement.
Hooke’s Law only applies within a spring’s elastic limit; stretching a spring too far can permanently deform it and this formula will no longer be accurate. For general educational use.
Last reviewed August 2026