The Website contains links to external archery resources: bow manufacturer specifications sheets, IBO and ASTM standards, hunting regulation databases, arrow brand spine charts, archery forums, and tuning guides. These links are provided as a convenience and do not constitute endorsement, sponsorship, or affiliation with those third parties. Arrow speed, FOC, weight, and spine calculations may vary due to input accuracy, bow model differences beyond IBO rating, arrow brand discrepancies, and real-world tuning variables. If you identify a calculation error or outdated specification, please contact us with the details — we verify against IBO and ASTM published standards and peer-reviewed archery physics before making corrections.
Terms of Service
The rules for using arrow-calculator.com — your archery calculator suite covering arrow speed, FOC, weight, and spine. These terms govern your relationship with Arrow Calculator — please read them before you run your first calculation or compare bow setups.
Arrow Calculator (the "Service") provides the Arrow Speed Calculator, Arrow FOC Calculator, Arrow Weight Calculator, Arrow Spine Calculator, kinetic energy and momentum estimators, and related archery tuning tools on arrow-calculator.com (the "Website") for bowhunters, competitive archers, bow technicians, archery retailers, and DIY tuning enthusiasts. By accessing or using the Website in any way — running a speed calculation, checking FOC balance, tallying arrow weight, selecting a spine, or comparing kinetic energy against hunting regulations — you agree to comply with these Terms of Service. If you disagree with any term or condition set forth here, your only recourse is to immediately discontinue your use of the Website.
We may update, revise, or replace these Terms of Service at any time, at our sole discretion. Changes take effect immediately upon being posted to the Website. The current version is always linked from the footer. You should review these Terms periodically — particularly after we update the IBO formula constants, refine the FOC or spine logic, add new calculation modes, or introduce additional archery tools — to ensure you remain in agreement with the governing rules.
You agree not to misuse the Website or its arrow speed calculation tools. Specifically, you will not:
Prohibited Actions
- Infringe any patent, trademark, trade secret, copyright, or proprietary right belonging to archery manufacturers, IBO, ASTM, or any third party
- Violate federal, state, provincial, or local laws — including hunting regulations, wildlife management codes, or archery competition rules in your jurisdiction
- Submit malicious code, attempt to breach our servers, or disrupt the calculation engine's normal operation
- Scrape, crawl, or bulk-download arrow speed, FOC, weight, or spine results, IBO formula data, archery terminology, or guide content for commercial resale
- Reverse-engineer, decompile, or extract the source code of the calculators, their formulas, or unit conversion logic
- Represent calculator output as a professional bow tuning certification, chronograph-verified measurement, or safety-approved hunting recommendation
- Use forged headers, impersonate another user, or disguise the origin of any request to the Website
- Overload the servers, attempt denial-of-service attacks, or interfere with the Website's availability for other archers
Unless you receive express written consent, you may not copy, reproduce, distribute, sell, resell, or commercially exploit any part of the Website — including the IBO formula implementation, FOC balance-point logic, spine deflection tables, or unit conversion logic. Individuals and businesses may use the calculators for personal, educational, and tuning purposes without restriction, provided they do not violate the prohibited actions above.
Please review our Privacy Policy for detailed information on how the Website handles data. In brief: the IBO rating, draw length, draw weight, arrow component weights, string weight, balance point, arrow length, and cam type you enter into any calculator are processed entirely within your browser. No bow setup or arrow build data leaves your device unless you explicitly copy the results or submit them through a contact form. Use of the Website is conditioned on your acceptance of both these Terms and the Privacy Policy.
The Service may impose limits on your access — including rate limits to prevent abuse, or full suspension for violations. We reserve the right to modify, suspend, or discontinue the Website or any calculator feature at any time without prior notice.
The arrow speed, FOC, weight, and spine calculators and all related tools are provided 'as is' and 'as available' without warranties of any kind — express or implied. This includes no warranties of merchantability, fitness for a particular hunting or competition purpose, accuracy of IBO adjustments or spine recommendations, or uninterrupted availability. Your use of the Service is at your own risk. Calculations are planning estimates for setup comparison only and should not be relied upon for critical decisions without independent chronograph verification, physical measurement, and professional bow tuning.
In no event shall Arrow Calculator be liable for any direct, indirect, incidental, special, consequential, or punitive damages arising from your use of the Website — including missed shots, equipment damage, regulatory non-compliance, or lost hunting opportunities caused by reliance on calculator outputs.
These Terms of Service are governed by the laws of the state in which the Website operator is registered, without regard to conflict-of-law principles. You agree to submit to the exclusive personal jurisdiction and venue of the courts located in that jurisdiction for any disputes arising out of or relating to your use of the Service.
If any provision of these Terms is determined to be invalid or unenforceable by a court of competent jurisdiction, that determination shall not affect the validity or enforceability of the remaining provisions. Any failure by Arrow Calculator to exercise or enforce any right or provision of these Terms shall not constitute a waiver of such right or provision.
You acknowledge that monetary damages alone may be insufficient to compensate for any breach of these Terms, and Arrow Calculator shall be entitled to seek injunctive or equitable relief to prevent or stop any violation, without foregoing any other rights or remedies available at law or in equity.
These Terms of Service, together with the Privacy Policy and any additional terms posted on specific pages of the Website, constitute the complete agreement between you and Arrow Calculator governing your access to and use of the arrow speed, FOC, weight, and spine calculators and all related services.
Your Privacy Is Protected
Your bow specs, arrow components, and draw measurements stay in your browser — we never see your setup. Review the Privacy Policy for details.
Fair & Responsible Use
Free for bowhunters and archers worldwide. No scraping, no bulk re-exports, no misrepresenting calculator results as professional tuning certifications.
Global Access, Local Standards
Available worldwide with support for imperial and metric units. Always verify your setup against local hunting regulations and competition rules.
Still Have Questions?
Our team is ready to clarify any part of these terms. We want you to use the calculators with confidence — and to understand exactly where IBO, FOC, weight, and spine estimates end and real-world chronograph and physical verification begin.
Important Notice
Use of arrow-calculator.com means you agree to comply with these Terms of Service. Arrow Calculator may modify these terms at any time; your continued use after changes are posted constitutes acceptance of the updated terms.