Heart Rate Zones Calculator

Get your five heart rate training zones in bpm — using the Karvonen method from your max and resting heart rate, or Joe Friel's zones from your lactate threshold.

Karvonen vs. LTHR — which method should you use?

The Karvonen method works off your heart rate reserve — the span between resting and max HR — so zones reflect the range you can actually use, not just a percentage of max. It's the better choice if you know your true max HR from a race or field test. The common 220 − age estimate can be off by 10–15 bpm in either direction, so treat zones built on it as a starting point.

LTHR zones (the Joe Friel standard used by TrainingPeaks) are anchored to your lactate threshold heart rate instead, which trained athletes can test far more repeatably than max HR: ride or run a 30-minute solo time trial and take your average HR for the final 20 minutes. If you train with a threshold-based plan or race with HR targets, use this method — and retest every few months as your fitness changes.