About the Heart Rate Zones
Heart Rate Zones is a free online Health & Fitness tool that runs entirely in your browser. There's nothing to install and no account to create — just open it and go.
Because Heart Rate Zones works client-side, your files are processed on your own device and are never uploaded to a server, keeping your data completely private.
Features
- Runs 100% in your browser — nothing is uploaded
- Free to use, with no sign-up and no limits
- Fast results with a clean, simple interface
- Works on desktop and mobile
How to use Heart Rate Zones
- Open Heart Rate Zones and load your file or input.
- Adjust the available options to fit your needs.
- Download or copy your result instantly.
Frequently asked questions
Is Heart Rate Zones free?
Yes — Heart Rate Zones is completely free, with no sign-up and no usage limits.
Are my files uploaded?
No. Heart Rate Zones runs entirely in your browser, so your files never leave your device.
Do I need to install anything?
No installation is required. Heart Rate Zones works directly in your web browser on desktop and mobile.