Health & Fitness
Heart Rate Zone Calculator
Heart Rate Zone Calculator is a browser-based calculator tool on CalcToolsBase. Map your five training heart-rate zones, from recovery to maximum effort. To use it, enter your values and view the result directly in your browser — no signup and nothing to install.
Heart Rate Zone Calculator takes your age in years and resting HR (bpm) — optional and gives back your target zones in beats per minute, applying age-based heart-rate formulas. It's a quick, browser-based way to find your heart-rate training zones.
About this calculator
Use the Heart Rate Zone Calculator to find your heart-rate training zones. It reads your age in years and resting HR (bpm) — optional, computes your target zones in beats per minute with age-based heart-rate formulas, and shows the result clearly labelled. Because the calculation happens in your browser, your figures never leave the page and there is nothing to install.
Zone boundaries are approximate and depend on the formula and your individual physiology. Treat them as training guidance for general fitness rather than precise thresholds.
How to use
- Enter your age in years for the five zones.
- Optionally add resting heart rate for Karvonen zones.
- Press Calculate to see all five zones in bpm.
- Train in the zone that matches your session goal.
Why use Heart Rate Zone Calculator
Fast
Calculations run in your browser. No round trip to a server.
Private
Your inputs never leave your device. Nothing is uploaded.
Free
No signup, no paywall, no ads-in-results, no watermarks.
Educational
Uses common estimation formulas for educational purposes. Results are not medical advice and should not replace professional guidance.
Mobile-ready
Optimised for phones, tablets, and desktops alike.
Transparent
Clear about formulas used and their limits, with disclaimers where they matter.
Common uses
Heart Rate Zone when starting a new programme
Heart Rate Zone in endurance-training plans
Heart Rate Zone when learning your max and zones
Heart Rate Zone for quick heart-rate reference
Heart Rate Zone for warm-up and recovery targets
Heart Rate Zone as a general training guide
Technical notes
Heart Rate Zone Calculator computes training zones as percentages of your maximum heart rate (≈ 220 − age).
A training estimate from the figures you enter; real results vary with fitness, terrain and conditions, so use it as a guide.
Nothing you type is uploaded — the calculation happens entirely on your device.
FAQ
What are the five heart-rate zones?
They run from Zone 1 recovery (very easy) through Zone 2 easy, Zone 3 aerobic, and Zone 4 threshold, up to Zone 5 maximum effort.
What is the Karvonen method?
Karvonen calculates zones from heart-rate reserve — maximum minus resting heart rate — then adds back resting HR, personalising zones to your fitness.
Which zone burns the most fat?
Lower, aerobic zones use a higher share of fat for fuel, but higher zones burn more total calories. Both have a place in training.
Does the Heart Rate Zone Calculator send my data to a server?
No. The Heart Rate Zone Calculator runs entirely in your browser — your inputs never leave your device, and nothing is uploaded or stored.
Worked example
With a max of 190 bpm, Zone 2 (60–70%) is 114–133 bpm and Zone 4 (80–90%) is 152–171 bpm — useful for pacing workouts.