Terms of Service

Bolt Calculator (the "Company") provides free online bolt calculators — a main bolt torque calculator (torque to clamping force and back through the K factor, with lubrication compensation, torque ranges, and strength checks) plus fastener weight and bolt shear tools — on bolt-calculator.com (the "Website") for mechanical engineers, maintenance technicians, fabricators, and students. By accessing or using the Website in any way — running a calculation, reading a guide, or citing a result — you agree to comply with these Terms of Service. If you object to any term or condition here, or to any guideline posted on the Website, your sole and exclusive remedy is to immediately discontinue use of the Website.

We may revise, modify, or replace these Terms of Service at any time at our sole discretion. Changes take effect immediately upon posting to this page, and the latest version is always linked from the Website footer. Because the Website is free and requires no account, posting is deemed sufficient notice. You should review these Terms periodically — particularly before relying on calculator output for a real assembly procedure or a purchasing decision.

All output from the Website — clamping force from torque, torque targets from preload, K-factor and lubrication adjustments, torque ranges, fastener set weights, and shear stress margins — is provided for informational, planning, and educational purposes only. It is not a manufacturer's torque specification, not an engineering drawing, not a joint design, not a code-compliance document, and not professional advice of any kind.

The Website does not replace a licensed professional engineer, a qualified fastener specialist, or the applicable engineering standards and the authority having jurisdiction. Grade selection, joint design, thread engagement, washer and gasket behavior, vibration control, and safe assembly procedures are project-specific and must be evaluated for every joint by qualified engineers. Nothing on this Website creates a professional relationship of any kind.

You agree not to post, transmit, or use the Website in any way that:

• Violates any applicable federal, state, provincial, or local law, including engineering codes and safety regulations where the work will be done
• Attempts to scrape, crawl, mirror, or bulk-download calculator results, torque and grade data tables, or guide content
• Reverse-engineers, decompiles, or extracts the calculation engines — the torque–preload relationship, K-factor and lubrication adjustments, and the shear and weight math — for reuse in another product
• Misrepresents calculator output as a manufacturer's certified torque specification, a professionally engineered joint design, or a code-compliant fastening assessment
• Infringes any patent, trademark, trade secret, copyright, or other proprietary right of any party
• Uses forged headers, rotating proxies, or false identifiers to disguise the origin of requests to the Website
• Disrupts, overloads, or interferes with the normal operation of the Website or its infrastructure

Unless you receive explicit written permission from the Company, you may not copy, reproduce, resell, or exploit any part of the Website for commercial purposes. Quoting a short result with attribution and a link in a forum post, lesson, or estimate note is welcomed; systematic republication is not.

The Website's software, calculation engines, original text, page designs, logos, and graphics are owned by the Company and protected by copyright and other intellectual-property laws.

Manufacturer names, fastener product lines, torque and strength standards, and technical documents referenced on the Website belong to their respective publishers. The Website independently implements publicly documented calculation methods — the torque–preload relationship T = K·F·d, the nut-factor approach with dry and lubricated K values, stress-area and property-class references aligned with ISO 898-1 and SAE grade practice, and the shear-stress treatment familiar from classical machine-design texts — and refers to those publications for identification and educational purposes only. This Website is not affiliated with, endorsed by, or sponsored by any fastener manufacturer or standards body, and calculator output is not a substitute for the manufacturer's published torque tables, the current editions of the referenced standards, or the judgment of your engineer. Where precise product data matters, consult the manufacturer's published data and the authority having jurisdiction.

Our Privacy Policy explains how the Company collects, uses, and discloses information, and is incorporated into these Terms by reference. In short: the inputs you enter — bolt diameter, K factor, torque or clamping force, lubrication condition, grade, and thread details — are processed locally in your browser and are not transmitted to or stored on our servers. Use of the Website constitutes acceptance of the Privacy Policy as well as these Terms.

The Website contains references to fastener products, K-factor values, torque tables, grades, brands, and third-party resources. These references are provided to help you find authoritative sources and are not intended to imply sponsorship, endorsement, or affiliation, or that any trade name, trademark, or logo may be used by you.

Calculator output may be affected by input accuracy, friction variance between coatings and lubricants, embedment and preload relaxation, tool calibration, temperature, and joint conditions the tool does not model. If you believe a formula, data value, or guide statement is incorrect, contact us with the page URL, your inputs, and the result you expected — we investigate every report and update content to the extent the authoritative sources allow.

The Website is funded by third-party advertising, including Google AdSense. Ads are clearly distinguished from calculator output and editorial content. We do not control, endorse, or warrant advertised products or services, and any dealings between you and an advertiser are solely between you and that advertiser. Advertising cookies and your opt-out choices are described in the Privacy Policy.

The Company may set limitations on your use of the Website, and may modify, suspend, or discontinue the Website — or any part of it — at any time, with or without notice, at its sole discretion.

THE WEBSITE AND ALL CALCULATORS, TORQUE AND GRADE DATA TABLES, REFERENCE VALUES, AND GUIDES ARE PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING WARRANTIES OF ACCURACY, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. YOUR USE IS ENTIRELY AT YOUR OWN RISK.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, IN NO EVENT SHALL THE COMPANY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES ARISING FROM YOUR USE OF (OR INABILITY TO USE) THE WEBSITE — INCLUDING DAMAGES FROM MIS-TORQUED JOINTS, WRONG GRADE SELECTION, BROKEN FASTENERS, STRIPPED THREADS, JOINT SLIPPAGE OR LEAKAGE, EQUIPMENT DAMAGE, ASSEMBLY DELAYS, INSPECTION FAILURES, COST OVERRUNS, LOST PROFITS, OR ERRORS IN K FACTORS, TORQUE VALUES, OR SHEAR CALCULATIONS. SOME JURISDICTIONS DO NOT ALLOW CERTAIN WARRANTY EXCLUSIONS OR LIABILITY LIMITATIONS, SO SOME OF THE ABOVE MAY NOT APPLY TO YOU.

These Terms of Service shall be governed by the laws of the United States, without regard to conflict-of-laws provisions. You and the Company agree to submit to the personal and exclusive jurisdiction of the courts located within the United States for any dispute arising from these Terms or your use of the Website.

If any provision of these Terms is held invalid or unenforceable by a court of competent jurisdiction, that holding shall not affect the validity or enforceability of the remaining provisions, which continue in full force. The Company's failure to enforce any right or provision shall not constitute a waiver of that right or provision, or of any further rights. These Terms, together with the Privacy Policy and the Disclaimer, constitute the entire agreement between you and the Company regarding the Website and supersede any prior agreements.

If you have questions about these Terms of Service, or need to report a violation of them, reach us via the contact page. We read every message and respond to legitimate inquiries.