HIIT Heart Rate Calculator

Find accurate HIIT heart rate zones for intervals. Adjust formulas, targets, and session structure easily. Stay efficient while training within safer cardiovascular limits daily.

Enter HIIT Training Inputs

Example Data Table

Profile Age Resting HR Formula Method Work Zone Recovery Zone Rounds
Sample Athlete 32 58 bpm Tanaka Heart rate reserve 166 - 175 bpm 135 - 147 bpm 9
Session Setup 40s work / 80s recovery 28-minute session 5-minute warm-up, 5-minute cool-down 1 bpm rounding

Formula Used

Maximum heart rate formulas

Fox method: Max HR = 220 − age

Tanaka method: Max HR = 208 − 0.7 × age

Gellish method: Max HR = 207 − 0.7 × age

Custom method: Max HR = user entered value

Target heart rate formulas

Percent of max method: Target HR = Max HR × intensity%

Heart rate reserve method: Target HR = Resting HR + ((Max HR − Resting HR) × intensity%)

Full interval rounds: Rounds = floor((session seconds − warm-up seconds − cool-down seconds) ÷ (work seconds + recovery seconds))

Estimated session average is the weighted midpoint of warm-up, work, recovery, and cool-down targets across their planned durations.

How to Use This Calculator

  1. Enter your age and resting heart rate.
  2. Select a maximum heart rate formula or choose a custom maximum value.
  3. Choose either heart rate reserve or percent of maximum heart rate.
  4. Set low and high intensities for warm-up, work, recovery, and cool-down phases.
  5. Add total session time, warm-up time, cool-down time, and interval lengths.
  6. Click the calculate button to show results above the form.
  7. Review zones, round count, estimated session average, and the graph.
  8. Use the CSV or PDF buttons to export your results.

FAQs

1. Which formula should I choose?

Tanaka is commonly used for general exercise planning. Fox is simple and familiar. Gellish gives another age-based estimate. A custom value works best when you already know your measured maximum heart rate.

2. What is the heart rate reserve method?

It uses both resting heart rate and estimated maximum heart rate. This often gives more personalized targets because fitter users usually have lower resting heart rates than less conditioned users.

3. Are higher work percentages always better?

Not always. Extremely high targets can reduce workout quality, shorten repeatable effort, and raise fatigue. Choose work zones that match your training age, recovery capacity, and session purpose.

4. Why include warm-up and cool-down zones?

They help structure the session safely. Warm-up targets prepare your cardiovascular system before hard intervals. Cool-down targets help reduce intensity gradually instead of stopping abruptly.

5. Why do I have leftover seconds?

Your interval block may not divide perfectly into equal work and recovery cycles. The calculator shows only full rounds and reports any unallocated seconds remaining.

6. Should I round targets to 5 or 10 bpm?

That depends on how you train. One-beat rounding is precise. Five or ten beats can be easier for treadmill sessions, group classes, or quick glances during intense intervals.

7. Can beginners use this calculator?

Yes, but beginners should use conservative work zones and longer recovery periods. Starting with fewer rounds and lower intensities usually improves consistency and reduces excessive fatigue.

8. Is this calculator a medical tool?

No. It is a training planner based on common formulas. It does not replace clinical testing, diagnosis, or personalized advice from a qualified healthcare professional.

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Max Heart RateTarget Heart RateTraining Zone CalculatorResting Heart RateFat Burn ZoneCardio Zone CalculatorAnaerobic Zone CalculatorAerobic Zone CalculatorHRV Score CalculatorHeart Rate Zones

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.