About this calculator

I hope you enjoy this tool and that it is useful to you! I created this site and I maintain it on my free time. Also, server cost me a few dollars every month, so if you want to support me, you can offer me a coffee :

...if you like 🙂

Honest content

No third-party ads, no affiliate links, no tracking cookies. Just honest content.

Questions or feedback?

If you see a problem or have any remarks, please contact me at antonin.info@protonmail.com.

Privacy & legal

This tool does not require an account and does not store any personal data such as names or email addresses. Your race settings and paces stay in your browser.

I use self-hosted analytics to understand which pages are used and to improve the site. Data is stored on servers I control and is not shared with advertisers.

The app is available worldwide. Local laws may give you additional privacy rights; if you have any questions about your data, please contact me.

Translations are generated with the help of AI and may contain errors or inaccuracies.

All results are estimates only and do not guarantee actual race performance. Always listen to your body and follow medical advice.