A simple calculator where you input your age (and optionally your resting heart rate) to find your safe & effective workout heart-rate zones (including a “Karvonen” method zone).

Target Heart Rate Calculator — Safe & Accurate

Target Heart Rate Calculator

Find your safe and effective workout heart-rate zones
How to Use?

  1. Enter your age
  2. (Optional) Enter resting heart rate
  3. Press Calculate
  4. View standard zones + Karvonen (accurate) method
  5. Use the share button to send your results

Why Use?

✔ Know your safe training intensity
✔ Prevent over-training
✔ Improve fat-burning efficiency
✔ Get accurate HR zones using science
✔ Perfect for gym, running, cycling, and weight loss

📋 Things to keep in mind!

  • The basic method (age-based) gives a general safe range, but the optional resting HR + Karvonen method gives more personalized zones (more accurate for many people).

  • These are guidelines. We do not replace individual medical advice-if you have heart conditions or are unsure about exercise intensity, consult a medical professional.

  • Your actual “safe” zone might vary depending on fitness level, medications, health conditions, etc.

  • For best results: measure your resting heart rate in the morning (while still, relaxed) for accuracy, and make sure your age entry is correct.

  • Using HR zones is helpful for structuring workouts: e.g., warming up in lower zones, doing intervals in higher zones, cooling down in moderate zones.

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