Heart Rate Zone Calculator

Tanaka (208 - 0.7*age) is the most accurate for most adults per modern research. The classic 220-age (Haskell) can be off by 10-15 bpm, especially for older adults.

It uses heart rate reserve (MHR - RHR) instead of just %MHR. Target HR = ((MHR-RHR) * intensity%) + RHR. It is more personalized when you know your resting heart rate.

Z2 (60-70% MHR) burns the highest percentage of calories from fat, but higher zones burn more total calories. For fat loss, a mix of Z2-Z3 plus occasional Z4-Z5 intervals works best.

Yes, the Heart Rate Zone Calculator is 100% free with no registration, no hidden fees, and no usage limits. All processing happens locally in your browser, ensuring complete privacy.

Absolutely. The Heart Rate Zone Calculator processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.

Yes, the Heart Rate Zone Calculator is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.

No account or registration is needed. Simply open the Heart Rate Zone Calculator in your browser and start using it immediately. There are no sign-up walls or usage restrictions.

Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.

The Heart Rate Zone Calculator works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. For the best experience, use the latest version of your preferred browser.

The most practical way is an age-based formula, which estimates your maximum heart rate (MHR) from a population average. This calculator offers four: Tanaka (208 - 0.7 x age), the recommended default for most adults; Haskell/Fox (220 - age), the well-known classic; Gulati (206 - 0.88 x age), derived from data on women; and Nes (211 - 0.64 x age) from the Norwegian HUNT study. Enter your age and the tool returns your estimated MHR in beats per minute instantly. Keep in mind these are estimates, and a true lab VO2-max or field test with a chest-strap monitor gives a personal number. For day-to-day training, the formula output is a solid starting point. Enter your age above and pick a formula to see your estimated max.

Each zone is a percentage band of your maximum heart rate tied to a specific training adaptation. Z1 Recovery (50-60%) is for warm-ups, cool-downs, and easy active recovery. Z2 Aerobic / Fat Burn (60-70%) builds your aerobic base and burns the highest percentage of calories from fat. Z3 Endurance (70-80%) improves aerobic capacity at a steady, sustainable effort. Z4 Threshold (80-90%) works your lactate threshold to raise sustainable speed and stamina. Z5 VO2 Max (90-100%) is for maximal intervals and sprints. Training across the right zones ensures easy days stay easy and hard days are hard enough to drive fitness. This calculator shows the exact bpm range, purpose, and example activity for each zone so you can match effort to intent. Enter your age to see all five mapped to your heart rate.

Because the two methods measure intensity differently. A plain %MHR zone takes a flat percentage of your maximum heart rate alone. The Karvonen method works from your heart rate reserve (HRR), the gap between your max and resting rates, using Target HR = (HRR x intensity%) + resting HR. Since it adds your resting heart rate back into every target, Karvonen produces higher, more individualized numbers, and the difference is largest if you have a low resting heart rate from regular training. That makes Karvonen useful for fit athletes whose plain %MHR targets feel too easy. This calculator shows standard %MHR zones from your age alone, then unlocks a second Karvonen set once you add your resting heart rate. Enter your resting rate above to compare both side by side.

Age-based formulas are reliable for general training but are not exact for any one person. They are built from population averages, so individual maximum heart rates vary by roughly 10 to 15 bpm above or below the predicted value. The classic 220 - age formula carries the most error, especially for older adults, which is why this tool defaults to the more accurate Tanaka equation and offers Gulati for women and Nes from a large fitness study. Adding your resting heart rate for Karvonen zones personalizes the targets further. For precise zones, a lab VO2-max test or a field threshold test with a chest-strap monitor is the gold standard. Treat the output as a well-grounded starting point you can refine against how efforts actually feel. Enter your details above to get your personalized estimate.

It depends on your goal, since each zone drives a different adaptation. For fat loss, lean on steady time in Z2 and Z3 to keep effort aerobic and sustainable. For endurance, build a Z2-Z3 base and add Z4 intervals to push your threshold upward. For a VO2-max session, stack hard Z4-Z5 intervals with Z1 recovery between efforts. For an easy day, keep the whole hour in light Z1-Z2 to promote recovery. This calculator includes a 60-minute workout planner that shows the suggested minutes per zone for each of these four goals as a simple bar, so you can see how an hour breaks down before you start. You can also copy a summary or download a CSV of your zones for your training log. Pick a goal in the planner above to see your minute-by-zone breakdown.