Zonta

Zonta is a simple, focused calculator that turns your age into clear heart-rate training zones, so you can train at the right intensity instead of guessing. Enter your age — or your own measured maximum heart rate if you know it — and Zonta instantly works out your estimated maximum and splits it into the five classic training zones, from easy recovery all the way up to maximum effort.

Each zone is shown as a clear beats-per-minute range with a short, plain-language label, so you know exactly what a steady endurance run should feel like versus a hard interval. It is the kind of reference you set once and glance at before a session, taking the mystery out of pacing your cardio. Everything is laid out for quick input and easy reading, with no sign-ups, no accounts and no clutter.

These zones are estimates based on common formulas, useful for general training but not a substitute for medical advice — check with a professional if you have any health concerns. Ready to train smarter? Enter your age and see your zones.