Terms of Service

1. Who we are

ExaCalc is an independent online hub of calculators, converters, and financial tools, built and operated by a small indie team. We are not a registered financial, medical, legal, or engineering firm. Contact us at indigoworks28@gmail.com.

2. Permitted use

You may use ExaCalc for personal, educational, non-commercial, and (subject to section 6 on the API) commercial purposes. You agree not to:

• Attempt to scrape, mirror, or bulk-download tool content or calculation results without a valid API subscription.
• Reverse-engineer or extract Pro features without a current paid subscription.
• Send more than 10 automated requests per second to any ExaCalc endpoint (sustained automated load beyond normal calculator use).
• Use ExaCalc for any unlawful purpose or to facilitate illegal activity.
• Attempt to interfere with, disrupt, or gain unauthorized access to our servers, networks, or other users' accounts.
• Republish substantial portions of ExaCalc's content as your own without explicit written permission.

3. Free accounts

Free accounts are not open yet. This section applies from the moment you can create one.

You never need an account to use ExaCalc's calculators and graphing tools. A free account adds saving, syncing and higher usage limits. If you create one:

• Eligibility. You must be 18 or older, provide a working email address that you control, and keep your details accurate. One person, one account. By continuing to sign in you confirm that you are 18 or older.
• Signing in. You sign in with a one-time code we email you, or with your Google account. You are responsible for the security of your email inbox and Google account and for everything done through your account. Tell us promptly if you think someone else has access.
• Limits and quotas. Free accounts have limits on how much you can save (history, favorites, scenarios, reminders, formulas) and on how often you can use certain features (for example PDF exports, AI questions, full step-by-step solutions and emailed results per day or month). Your current limits are shown in your account. We may change limits, and we will not use a limit change to delete your existing saved items without notice.
• Acceptable use. In addition to section 2, you agree not to: use "Email me this result" or any other feature to send messages to anyone but yourself (results are only ever sent to your own account address, and you must not try to change that); request sign-in codes for email addresses that are not yours or flood the sign-in system; create multiple or disposable-email accounts to get around limits or quotas; use scripts or bots against account features; or store unlawful content, malware or other people's confidential information in your saved items.
• Reminders and saved data. Reminders, dates and rates are a convenience, not a guarantee. They may be late, missed or wrong, so always confirm deadlines and figures with the official source. We aim to keep your saved data safe, but we do not promise the service is uninterrupted or error-free, so keep your own copy of anything important. You can download your data from your account.
• Email. We send sign-in codes, reminders you set, results you ask for and account notices. Marketing email is separate: it is off unless you opt in, and you can unsubscribe at any time from your account or from any marketing email.
• Deleting your account. You can delete your account at any time from your account settings. Sign-in stops immediately and your saved data is permanently erased after a short grace period, as described in our Privacy Policy. An active paid subscription is cancelled but is not refunded automatically (see section 5).
• Suspension and termination by us. We may limit, suspend or close an account, with or without notice, if it breaches these terms, is used to abuse or attack the service, or if we are required to by law. We may also stop offering free accounts or particular features; if we do, we will give reasonable notice where we can and let you export your data first.

4. Accuracy and disclaimer

ExaCalc provides calculations, conversions, and estimates on an "as is" and "as available" basis for informational and educational purposes only. Every tool is developed and tested against authoritative references, but:

• Financial tools. Results do not constitute professional financial, tax, investment, or accounting advice, and exchange rates and tax rules change frequently. Always consult a licensed financial or tax professional before making decisions based on our output.
• For medical and health tools, including BMI, BMR, TDEE, dosage calculators, and clinical scoring tools, our output is for general information only and is not medical advice. Never substitute our results for consultation with a qualified clinician.
• Clinical and drug-dosing tools (for example clinical risk and severity scores, drug dose, infusion-rate, renal-function and opioid-conversion calculators, and paediatric dosing). These are decision-support references for licensed healthcare professionals, not medical devices and not a diagnosis, treatment recommendation or substitute for clinical judgement. Do not use them in an emergency or as the only basis for a treatment or dosing decision. Always check every dose and score independently against current product labelling, guidelines and your institution's protocols, and remember that scores can be wrong for a given patient. Do not type patient names, ID numbers or other identifying details into any tool, and do not save them to an account.
• Laboratory and biomedical tools (for example molecular weight, primer melting temperature, dilution and cell-count calculators) are for education and research planning. They are not diagnostic and must be verified before use in an experiment, clinical or safety-critical setting.
• Engineering and scientific tools: results must not be used as the sole basis for structural, aerospace, chemical, electrical, or any other life-safety engineering calculation. Always verify with the appropriate professional standard and a qualified, licensed engineer.
• Legal tools produce outputs that are for illustrative purposes only and do not constitute legal advice; consult a qualified attorney in your jurisdiction.
• AI-generated explanations (such as "Explain this for me") are produced automatically, may be incomplete or wrong, and are not advice of any kind.

We make no warranty, express or implied, that results are error-free, complete, current, or fit for any particular purpose. You are responsible for checking that a result makes sense before relying on it.

5. Pro subscriptions and billing

If you subscribe to a Pro or Industry Suite plan:

• Billing is processed by a third-party payment provider (currently Dodo Payments or Razorpay). We never receive or store your card details.
• Subscriptions automatically renew at the end of each billing period (monthly or annual) unless cancelled before the renewal date.
• You may cancel at any time from your profile page. Access to Pro features continues until the end of your paid billing period.
• Refunds are evaluated case-by-case. We honor refund requests made within 14 days of the initial purchase if you have not made significant use of Pro features. Email us to request a refund.
• Prices may change. We will give at least 30 days' notice before changing the price of an active subscription.

6. API access

Access to the ExaCalc API (/api/v1/) is subject to rate limits that vary by plan (free: 100 requests/day; pro: 1,000/day; enterprise: 10,000/day). API keys must not be shared publicly or embedded in client-side code. We reserve the right to suspend API access for abuse or violation of these terms without prior notice.

7. Embeddable widgets

You may embed ExaCalc calculators on external websites using our official embed.js script and the provided HTML snippet. Embedded tools must retain the "Powered by ExaCalc" attribution link. Stripping attribution or serving the embed script from your own domain is not permitted.

8. Intellectual property

The source code, UI design, branding, and original content of ExaCalc are our intellectual property. The mathematical formulas themselves, including compound interest, Ohm's law, and the Pythagorean theorem, are part of the public domain and belong to humanity.

You may link to, embed, screenshot, or quote individual tool results for personal, editorial, or educational use with attribution. You may not republish large portions of our content as your own, sell access to our tools, or create derivative works of our codebase without explicit written permission.

9. User-contributed content

If you submit feedback, bug reports, custom formulas, feature suggestions, or any other content, you grant us a royalty-free, worldwide, perpetual license to use, modify, and incorporate that content into ExaCalc for the purpose of improving the service. We will not disclose your identity in connection with contributed content without your permission.

10. Affiliate and partner links

Some tool pages display affiliate or partner links to external services (banks, brokerages, insurance providers, and similar). When you click through and complete a qualifying transaction, we may earn a commission at no additional cost to you. We only feature services we have reviewed, and affiliate relationships never influence the accuracy or neutrality of our calculations.

11. Third-party links and services

ExaCalc may contain links to external websites or services, and shows ads served by third parties. We are not responsible for the content, privacy practices, or availability of third-party sites or ads. Links do not imply endorsement unless explicitly stated.

12. Limitation of liability

To the maximum extent permitted by applicable law, ExaCalc and its maintainers, employees, and contractors are not liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of, or inability to use, the site or its outputs, including but not limited to lost profits, missed investment returns, or adverse medical or engineering outcomes.

Our total aggregate liability for any direct claim shall not exceed the greater of: (a) the total amount you paid us in the 12 months immediately preceding the claim, or (b) USD 100 if you have not made any payment to us.

13. Indemnification

You agree to indemnify and hold harmless ExaCalc and its maintainers from any claims, damages, losses, or expenses (including reasonable legal fees) arising from your use of the site in violation of these terms or applicable law.

14. Termination

We reserve the right to suspend or terminate access to ExaCalc or a specific account if these terms are violated, with or without notice (see also section 3). You may stop using the service, or delete your account, at any time. Sections 4, 8, 12, and 13 survive termination.

15. Governing law

These terms are governed by the laws of India. Any disputes will be resolved in the courts of India unless mandatory consumer-protection law in your jurisdiction requires otherwise. Nothing in these terms limits any statutory rights you have as a consumer under applicable law.

16. Changes to these terms

We may update these terms from time to time. When we do, we update the "Last updated" date at the top. For material changes, we will notify account holders and Pro subscribers by email at least 14 days before the new terms take effect. Continued use of ExaCalc after that date constitutes acceptance of the updated terms.

17. Contact

Questions about these terms? Email indigoworks28@gmail.com. We read every message and respond as quickly as we can.