Spring Calculator Professional
Spring Calculator Professional
The spring-design engine engineers and manufacturers have trusted for decades, running in any browser with nothing to install. Watch a live 3D spring redraw as you type — or give the Solver your constraints and let it find the design.
Nothing to install · Windows, Mac & Linux · Runs in any modern browser
No card required to look around — subscribe from £40/month when you’re ready to design.
Each one calculated with the specifics that actually matter to it — not a single formula stretched to cover them all.
Calculate, design, or let the Solver find it from your constraints — set up by an AI-assisted wizard. Then Goodman fatigue and relaxation from our own laboratory data.
Loops usually fail first, so loop stress gets its own Goodman diagram. A wide range of end forms and options models complex real-world springs — and every one exports to CAD.
Leg lengths, angular positions, torque and wind-up diameter reduction — single or double, round or rectangular wire.
The progressive rate as coils bottom out, and telescoping right down to solid — calculated, not approximated.
Die springs and anything else that has to pack maximum load and rate into minimum space — square or rectangular section, wound on flat or on edge.
Barrel, hourglass, dual-pitch — define the profile coil by coil and the engine models every coil individually.
Hundreds of spring manufacturers and thousands of engineers around the world design with Spring Calculator Professional. Fatigue, relaxation, tolerances, CAD-ready geometry and a full design record — not three inputs and an answer.
A real 3D model of your spring that redraws the instant you change a value. Rotate it, zoom in and inspect the geometry from any angle as you design — not a picture, the actual model.
See it redraw as values change →
Set the loads, rates and dimensions you have to hit, and the Solver searches for designs that satisfy every constraint — turning hours of iteration into seconds. Describe the job in plain English and it will set the constraints up for you.
Watch it work through a real brief →
Send a read-only link to a customer or colleague. They open the spring, its 3D drawing and every calculated result straight in their browser — no login, no account, nothing to install.
See what the recipient sees →
Export precise geometry as STEP or IGES — including the swivel hooks, coned ends and conical profiles you would otherwise lose an afternoon modelling by hand. Plus print-ready PDF reports of the full design, for the people who need paper.
See the exports and reports →
Stresses, fatigue life by Goodman, relaxation, tolerances and full operating data — the same engine as the desktop standard, unchanged. Zero install, and always the current version the moment you load the page.
Take the full walkthrough →The formulae are published — anyone can look them up. The material data behind them is the hard part, and ours comes from decades of testing real springs to destruction in the Institute’s own laboratories. That is what this calculator is actually built on.
Relaxation mapped across stress, temperature and time. Stress limits and fatigue data from our own testing — held alongside the BS, EN, SMI and JIS limits for the same material, so you can design to whichever standard you are held to and see how they differ.
Design, tolerance and material standards from around the world — British, European, German, American, Japanese, Chinese, Indian and ISO. Not one region’s practice with the rest bolted on afterwards.
The people writing this code also consult for the spring industry and deliver its training courses. Nothing here was copied out of a textbook — and when you ask a question about your spring, the answer comes from someone who designs them.
Spring Calculator Professional comes out of a working institute — testing laboratories, failure investigation, shot peening, training and technical support for over 200 member organisations worldwide. It is the same knowledge, in software form.
Independent load & torque, fatigue and materials testing to national and international standards — ISO 9001 certified verification that your springs meet specification.
ist.org.uk →
In-depth, impartial reporting on springs that have failed in service. SEM imaging, hardness testing and microstructural analysis to find the root cause — with recommendations to stop it happening again.
ist.org.uk →
Practical spring design courses delivered as scheduled open training, in-house at your site, or online — plus dedicated Spring Calculator Professional training.
ist.org.uk →
Shot peening for springs and precision components, inducing the compressive residual stresses that extend fatigue life. Over 40 years of technical know-how, steel and glass media, ISO 9001 quality controlled.
ist.org.uk →
Unlimited technical support, access to over 350 spring technology research reports, and member discounts on software, testing and training. Over 200 member organisations worldwide, from material suppliers to spring makers and end users.
ist.org.uk →
Spring Calculator Professional for Windows — the desktop standard behind this application, with the additional spring types and production tools a spring maker needs.
ist.org.uk →Calculate from geometry you already know. Design from the loads and positions the application needs. Or describe the job in plain English and let the Solver find the spring.
Watch the walkthrough →Three worked examples · no sign-up needed to look
The full professional tool, running wherever you do — office, workshop or factory floor.
Open a browser and start designing. No downloads, licences to deploy or IT tickets.
Every improvement and engine update reaches you the moment you load the page.
If it runs a modern browser, it runs the calculator — the same professional tool on every operating system.
45+ short video tutorials from the Institute of Spring Technology, built right into the calculator. Here’s a taste.
The full tutorial library is one click away inside the calculator — open Tutorials & Learning from any spring designer.
£40 per spring type per month, or all six for £150. No minimum subscription period.
Start designing →No card required to look around
Add or remove spring types at any time.
Open a browser and you are designing — nothing to install, nothing to deploy, and always the current version. On Windows, Mac or Linux, wherever the work is.