Z1 to Z5 from your own numbers — max-HR formulas, the Karvonen method and the truth about the fat-burning zone.
HRmax by Fox, Tanaka and Gulati — with the spread shown, because the formulas disagree by design.
Training targets from heart-rate reserve — the method that personalises zones with your resting HR.
Your complete Z1–Z5 table from age and resting HR, Karvonen-anchored — the zones watches try to guess.
The classic 60–70% zone computed — alongside the honest physiology of what 'fat-burning zone' actually means.
Your 1-minute post-exercise HR drop against the prognostic bands from the Cleveland Clinic research.
Where your morning RHR sits among population and athlete bands — and what trends in it signal.
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