Calculate training heart rate zones by age
OnlineTools360 is a free collection of online tools built for developers, designers, and content creators. Every tool runs entirely in your browser, so your tool inputs stay on your device and are not sent to us, stored, or tracked.
We believe developer tools should be free, fast, and private. No sign-ups, no paywalls, no data harvesting. Just open the tool, use it, and move on with your day.
Every tool on OnlineTools360 is built with client-side JavaScript. When you paste JSON to format, encode a string to Base64, or generate a password, all of that processing happens right in your browser. Nothing leaves your device. We can't see your data even if we wanted to — because it never reaches us.
We offer a growing collection of free tools spanning development, design, writing, security, and SEO categories. These include PDF tools, image converters, hash generators, password tools, color utilities, text manipulation tools, calculators, SEO analyzers, and much more — all running entirely in your browser.
OnlineTools360 was created by an independent developer passionate about making useful tools accessible to everyone. The site is designed to be lightweight, fast-loading, and completely self-sustaining.
OnlineTools360 is maintained as a practical utility library. We prioritize fixes that make a tool more accurate, easier to use on mobile, clearer for first-time visitors, or safer for private browser-side work.
Have a question, suggestion, or found a bug? We'd love to hear from you.
Thanks for your feedback!
We'll review it and get back to you if needed.
We typically respond within 24-48 hours.
Last updated: August 10, 2026
OnlineTools360 ("we", "us", or "our") operates the OnlineTools360 website. This page informs you of our policies regarding the collection, use, and disclosure of information when you use our service.
Short version: All tools run entirely in your browser. The data you input into our tools (JSON, text, passwords, files, etc.) is not transmitted to our servers and is not stored outside your device.
We use essential browser storage to remember your theme, favorites, layout, recent tools, and privacy choice. These preferences stay on your device and are needed to provide the features you request.
Google Analytics and Google AdSense are optional. Their scripts and storage remain disabled until you allow the relevant category. Google Analytics helps us understand visits and tool usage. Google AdSense displays advertisements and may use cookies, device identifiers, or similar technologies, including for personalized advertising where permitted.
You can accept, reject, or change these choices at any time using . You can also manage personalized advertising through Google Ads Settings. Learn more in Google's explanation of data used on partner sites.
All tools on OnlineTools360 process data locally in your web browser using client-side JavaScript. No input data is ever sent to our servers. We cannot access, view, or store the data you enter into any of our tools. This applies to all tools across every category.
Our website may contain links to third-party websites or services that are not operated by us. We have no control over and assume no responsibility for the content, privacy policies, or practices of any third-party sites or services.
Our service is not directed to anyone under the age of 13. We do not knowingly collect personally identifiable information from children under 13.
We may update our Privacy Policy from time to time. We will notify you of any changes by posting the new Privacy Policy on this page and updating the "last updated" date.
If you have any questions about this Privacy Policy, please contact us at [email protected].
Last updated: February 2025
By accessing and using OnlineTools360, you agree to be bound by these Terms of Service.
OnlineTools360 provides free online tools for developers, designers, and content creators. You may use our tools for personal and commercial purposes. You agree not to misuse our services or help anyone else do so.
Our tools are provided "as is" without warranties of any kind, either express or implied. While we strive to ensure accuracy and reliability, we do not guarantee that the tools will be error-free or uninterrupted. You are responsible for verifying any output generated by our tools before using it in production or critical applications.
The OnlineTools360 name, logo, and website design are our intellectual property. The tools themselves are freely available for use, but you may not clone, rebrand, or redistribute our website as your own without permission.
In no event shall OnlineTools360 be liable for any indirect, incidental, special, consequential, or punitive damages resulting from your use of or inability to use the service. This includes but is not limited to damages for loss of profits, data, or other intangible losses.
Our website contains links to third-party websites and services. We are not responsible for the content or practices of these external sites. Your interactions with third-party services are solely between you and that third party.
OnlineTools360 may display advertisements provided by Google AdSense. The presence of advertisements does not constitute an endorsement of the advertised products or services.
We reserve the right to modify these terms at any time. Continued use of the website after changes constitutes acceptance of the updated terms.
Questions about these terms? Contact us at [email protected].
OnlineTools360 is built around small, focused utilities. Feedback is useful when it points to a specific tool, input, browser, or workflow where the result could be clearer or more accurate.
Send tool ideas to [email protected] with the subject line "Feature Request". Useful suggestions describe the input, the expected output, and why the task matters.
Include the tool name, your browser, the exact input when possible, what you expected, and what happened instead. Screenshots are helpful for layout, copy button, file handling, and mobile issues.
If a calculator, converter, reference table, or generated output looks wrong, send the example and the source you used to verify it. Accuracy fixes are prioritized over cosmetic changes.
Do not send passwords, private documents, customer data, or confidential text in support messages. The tools process input in your browser, and support requests should use safe sample data only.
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