Every calculation runs locally in your browser. Distances, times and weights you type in are never uploaded.
What we collect
- Anonymous traffic statistics (page views, country) to see which tools are useful.
- If you voluntarily submit a race result, only distance, time, age and gender are stored — no name, location or device ID.
Cookies and advertising
No cross-site tracking cookies are used. If advertising is added later, this page will be updated.
Contact
Questions? Reach us via the contact page.
Gear runners ask about
GPS running watch
Pace, laps and alerts on your wrist
Chest strap heart-rate monitor
More reliable than wrist-based HR
Race day running shoes
Lightweight shoes for tempo and race pace
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