Extension spring calculator

Find a stock extension spring from your working length and force, or design your own spring and check it against EN 13906-2.

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Link parameters for engineers, ERP and AI assistants

Every input can be set in the web address, so a link opens the exact result. Use it to save a search, send it to a colleague or let an AI assistant find a spring for you.

Example · Find a spring

https://axispring.com/en-se/pages/extension-spring-calculator?L=80&F=25&tol=10&od=16

Example · Design a spring

https://axispring.com/en-se/pages/extension-spring-calculator?tab=design&dmat=sh&dd=2&dmode=dm&dD=15&dn=20&dl1=100&dl2=120
L, F
Working length L (mm), Force F at L (N)
L2, F2
Second length L2 (mm), Force F2 at L2 (N)
tol
Force tolerance: 5 · 10 · 15 · 20 · 30 (%)
od, l0
Max outer diameter Do, Free length L0 (mm)
d, travel
Wire diameter d, Remaining extension to L1, at least (mm)
mat, stock
carbon · stainless · stock=1
tab=design
dmat (sh · dh · ss), dd (d, mm), dmode (do · dm · di), dD (mm), dn (n), dl0 (L0, mm, empty = full German loop), df0 (F0, N, empty = typical value), dl1, dl2 (mm), dyn (1 = dynamically loaded)