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5 Heart Rate Zones Calculator

Your complete Z1–Z5 table from age and resting HR, Karvonen-anchored — the zones watches try to guess.

Z1 recovery (50–60%)
Z2 endurance (60–70%)
Z3 tempo (70–80%)
Z4 threshold (80–90%)
Z5 max (90–100%)

The 80/20 finding behind zone training: elite endurance athletes across sports spend ~80% of sessions in Z1–Z2 and reserve real intensity for the rest — recreational athletes typically invert this into a grey Z3 mush. Zone 2's marker is conversational pace: full sentences, slightly effortful.

Formula

each zone = RHR + band% × (HRmax − RHR), Tanaka HRmax
Sources: Seiler S, Int J Sports Physiol Perform 2010 — intensity distribution

For general information only — not medical or training advice. Estimates vary between individuals; consult a qualified professional before changing your exercise or nutrition routine.

Your complete Z1–Z5 table from age and resting HR, Karvonen-anchored — the zones watches try to guess. The 5 Heart Rate Zones Calculator is a free, private heart rate zones tool — every result computes instantly in your browser with no sign-up and no data upload.

About 5 Heart Rate Zones Calculator

The 80/20 finding behind zone training: elite endurance athletes across sports spend ~80% of sessions in Z1–Z2 and reserve real intensity for the rest — recreational athletes typically invert this into a grey Z3 mush. It applies each zone = RHR + band% × (HRmax − RHR), Tanaka HRmax. Use the 5 Heart Rate Zones Calculator to get an instant, clearly-explained result with the working shown step by step — free, private and with the source method cited.

How to use 5 Heart Rate Zones Calculator

  1. 1Enter your details in the 5 Heart Rate Zones Calculator input fields above.
  2. 2The result updates instantly with the working and reference bands shown.
  3. 3Adjust any value to explore how it changes the outcome — it's free and unlimited.

Why use 5 Heart Rate Zones Calculator?

  • Instant heart rate zones result that recomputes as you type — no waiting, no page reloads
  • 100% client-side: your health data never leaves your browser
  • Shows the actual formula and your numbers substituted in, so you can see exactly how the result is reached
  • Based on published, citable sources (Seiler S, Int J Sports Physiol Perform 2010 — intensity distribution)
  • Free forever with no sign-up, account or app install

Frequently asked questions

How does the 5 Heart Rate Zones Calculator work?+

The 80/20 finding behind zone training: elite endurance athletes across sports spend ~80% of sessions in Z1–Z2 and reserve real intensity for the rest — recreational athletes typically invert this into a grey Z3 mush. The calculation uses the formula: each zone = RHR + band% × (HRmax − RHR), Tanaka HRmax. Everything runs instantly in your browser as you type — your inputs are never uploaded.

Is the 5 Heart Rate Zones Calculator accurate, and what is it based on?+

The method is traceable to authoritative sources: Seiler S, Int J Sports Physiol Perform 2010 — intensity distribution. Results are estimates — individual variation always applies, so treat the output as a well-grounded starting point.

Is the 5 Heart Rate Zones Calculator free and private?+

Yes. It's completely free with no sign-up, and all computation happens locally in your browser, so none of your health data ever leaves your device.

Can I use this for medical decisions?+

This tool is for general fitness information only, not medical or training advice. Consult a professional before changing your routine.

What can I use the 5 Heart Rate Zones Calculator for?+

It's commonly used for heart rate zones, zone 2 heart rate, 5 zones training. Your complete Z1–Z5 table from age and resting HR, Karvonen-anchored — the zones watches try to guess.

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