Heart Rate Zone Calculator
Calculate your 5 heart rate training zones using the Karvonen formula.
| Zone | Name | BPM Range |
|---|---|---|
| Z1 | Recovery | 128–140 bpm |
| Z2 | Aerobic Base | 140–153 bpm |
| Z3 | Aerobic Tempo | 153–165 bpm |
| Z4 | Anaerobic Threshold | 165–178 bpm |
| Z5 | VOâ‚‚ Max | 178–190 bpm |
The 220−age formula is an estimate; individual max heart rate can vary ±10–20 bpm. For precise zones, consider a supervised field test or VO₂ max lab test.
About Heart Rate Zone Calculator
This tool calculates your five heart-rate training zones using either the Karvonen (Heart Rate Reserve) or Simple (percentage of max HR) formula. Enter your age and resting heart rate to instantly see personalized BPM targets for every zone — from easy recovery efforts in Zone 1 to all-out VO₂ max intervals in Zone 5. The Karvonen method is generally more accurate because it accounts for your fitness baseline via resting heart rate, while the simple method offers a quick estimate using only age-predicted max HR.
Private & free — this tool runs entirely in your browser.