Terms of Service

Effective November 7, 2026

These terms are an agreement between you and Brian Glen ("we", "us"), who operates opensus, a suspension design tool for race cars. By creating an account or using opensus you agree to them. If you don't agree, please don't use opensus.

1. Engineering results

opensus calculates suspension geometry, forces, compliance and loads from the inputs you give it, using models with stated simplifications: rigid links, simplified tire and damper models, and assumed load cases. Results can be wrong because of those simplifications, because of input mistakes, or because of errors in the software. Do not rely on opensus alone for any decision affecting safety. Verify results independently, apply appropriate safety factors, and test parts and vehicles before use. Motorsport is dangerous; you accept the risks of building and driving anything you design.

2. Your account

You must be at least 13 years old, and old enough to form a binding contract where you live or have a parent's or guardian's permission. Give accurate information, keep your password safe, and tell us if you think someone else has used your account. You are responsible for what happens under your account. One person per account.

3. Free and Pro plans

You can use opensus's design and analysis tools for free. Downloading and exporting files requires a Pro subscription. We may change which features are in each plan; if a change takes away a Pro feature you pay for, we will tell you in advance.

4. Payments and cancellation

• Pro is billed in advance for each billing period (currently monthly) through Stripe, at the price shown when you subscribe, plus any applicable taxes.
• Your subscription renews automatically at the end of each period until you cancel. Cancel any time in Account settings under "Manage billing".
• When you cancel, Pro stays active until the end of the period you have paid for, then your account returns to the free plan. We don't refund partial periods, except where the law requires.
• We may change prices. We will give you at least 30 days' notice, and the new price applies from your next renewal, so you can cancel first.
• If a payment fails, Pro features may pause until it is resolved.

5. Your designs and content

You own your designs and anything else you create in opensus. Your designs are stored in your own browser, not on our servers. When you send us feedback, including any design or files you attach, you allow us to use it to investigate, fix and improve opensus, and we may use your suggestions without owing you anything. We handle it as described in the Privacy Policy.

6. Acceptable use

Don't:

• break the law, or infringe anyone's rights, using opensus;
• try to get around the subscription, access other people's accounts or data, or probe, disrupt or overload the service;
• copy, resell or redistribute opensus or its exports as a competing service, or scrape it with automated tools;
• upload malware or anything harmful in feedback attachments.

7. opensus itself

opensus, its software and its design belong to us. We give you a personal, non-transferable right to use it under these terms. Files you export are yours to use for your own projects.

8. Changes and availability

We may change, add or remove features, and opensus may sometimes be unavailable. If we ever shut opensus down, we will give paying subscribers reasonable notice and refund any unused prepaid period.

9. Ending your account

You can stop using opensus and ask us to delete your account at any time. We may suspend or close accounts that break these terms or put the service or other users at risk; where reasonable we will tell you first and explain why. Sections 1, 5, 10, 11 and 12 continue after your account ends.

10. Disclaimer

opensus is provided "as is" and "as available", without warranties of any kind, express or implied, including fitness for a particular purpose, accuracy of results, and non-infringement, to the fullest extent the law allows.

11. Limitation of liability

To the fullest extent the law allows, we are not liable for any indirect, incidental, special, consequential or punitive damages, or for loss of data, profits or business, or for any damage, injury or loss arising from parts, vehicles or decisions based on opensus results. Our total liability for any claim relating to opensus is limited to the amount you paid us in the 12 months before the claim, or $50 if greater.

Some places don't allow these limits, so they apply to you only as far as your local law permits. Nothing in these terms limits liability that cannot be limited by law.

12. Governing law and disputes

These terms are governed by the laws of the State of California, USA, without regard to its conflict of law rules. Any dispute will be handled in the state or federal courts located in California, and you and we agree to their jurisdiction. If you are a consumer living elsewhere, you keep any protections your local law gives you. Before going to court, please email us so we can try to resolve it.

13. Changes to these terms

We may update these terms. We will change the date above, and for significant changes we will tell account holders by email or in the app at least 30 days before they apply. If you keep using opensus after that, the new terms apply.

14. General

These terms and the Privacy Policy are the whole agreement between us about opensus. If any part is found unenforceable, the rest still applies. Not enforcing a term is not a waiver of it. You may not transfer these terms; we may transfer them to a new owner of opensus.

Contact

Brian Glen, support@opensus.app.