Pricing
Simple pricing. A fraction of what other tools charge.
Start free. Try Student or Pro free for 3 days: nothing is charged until the trial ends, and you can cancel any time before then. All prices are in US dollars.
Plans
Typical online structural tools cost $10–$139 per month. Student works out at about $2/month, billed once a year. Taxes are added at checkout where required. See the refund policy.
Free trial
How the free trial works
Student and Pro start with 3 days free. One free trial per account.
Choose a plan
Pick Student or Pro (Pro yearly or monthly). Sign in, then add a payment card at checkout. Nothing is charged today.
3 days free, full access
Everything in the plan is unlocked straight away: 3D, any model size, the step-by-step report, code export and combinations.
Charged unless you cancel
After the trial the plan you chose is charged automatically (Student or Pro). Cancel before the trial ends and you pay nothing.
Compare plans
What each plan includes
Numeric values need a (free) account on every plan: signed out you see the diagram shapes only. Free and Student are for non-commercial use; commercial work needs Pro or Lifetime.
FAQ
Pricing and billing questions
How does the free trial work, and will I be reminded before I am charged?
Student and Pro start with a 3-day free trial. You add a card at checkout, nothing is charged during the trial, and when it ends the plan you chose is charged automatically. We aim to send a reminder e-mail before the trial ends, but please do not rely on it: the trial end date is shown under Manage subscription. There is one free trial per account.
Can I cancel any time?
Yes. Choose Manage subscription on your plan card above. If you cancel during the trial you are not charged. If you cancel later, you keep access until the end of the period you already paid for and are not billed again.
What is your refund policy?
The first payment of a yearly plan, and a Lifetime purchase, can be refunded in full within 14 days, no questions asked. Monthly renewals are not refundable. The details are on the refund policy page.
What does “Student” mean?
The Student plan is for non-commercial use: studying, teaching, research and personal projects. It runs on the honour system: we do not ask for proof of enrolment. If you use StiffStruct for paid or client work, please choose Pro or Lifetime.
Can I use StiffStruct for commercial work?
Yes, with the Pro or Lifetime plan. Pro also lets you put your name, company and logo on reports and gives you priority e-mail support. As always, results must be checked by a qualified engineer (see the terms).
Which payment methods do you accept? What about tax?
Payments are processed by Dodo Payments, which accepts cards and other payment methods depending on your country. Prices are in US dollars (your bank may convert them). Sales tax, VAT or GST is added at checkout where it applies.
What happens to my models if my plan ends?
Nothing is lost. Your models are stored in your own browser and are never deleted when a plan ends. You simply go back to the Free plan, which shows the diagram shapes without values. Subscribe again any time to see everything.
Will I get an invoice?
Yes. Dodo Payments e-mails a receipt for every payment, and invoices are available under Manage subscription. If you need your company details on an invoice, add them at checkout.
Can I switch from monthly to yearly, or to another plan?
Yes. Use Manage subscription, or write to us through the contact page (topic: billing) and we will change it for you.