Heart Rate Calculator
Find your maximum and target heart rates for exercise, with Karvonen training zones based on your age and resting heart rate.
Heart Rate Calculator — input your values
What does this health calculator do?
This heart rate calculator estimates your maximum heart rate with the classic 220-minus-age formula and the Tanaka alternative, then builds your exercise target zones. It also computes your heart rate reserve — the gap between resting and maximum — for the Karvonen method, which personalizes zones using your resting heart rate.
You get a table of four zones — light, moderate, vigorous and peak — each showing the percentage of maximum heart rate and the corresponding beats per minute, calculated both ways so you can train by whichever method you prefer.
Heart rate estimates are population averages; medications and individual variation can shift them. Use them as a general training guide and talk to a doctor before starting a new exercise program, especially if you have heart conditions.
Formula and variables
Tanaka alternative: max HR = 208 − (0.7 × age), often preferred for adults over 40.
| Symbol | Meaning |
|---|---|
| max | Estimated maximum heart rate (220 − age) |
| resting | Resting heart rate in bpm |
| % | Zone intensity, e.g. 0.50–0.70 for moderate |
Worked example
A 30-year-old with a resting heart rate of 60 bpm.
- Max HR = 220 − 30 = 190 bpm.
- Reserve = 190 − 60 = 130 bpm.
- Moderate (50–70% of max) = 95–133 bpm.
- Karvonen moderate = 60 + (0.50–0.70 × 130) = 125–151 bpm.
Answer: Max HR 190 bpm; moderate zone 95–133 bpm (max-based) or 125–151 bpm (Karvonen).
Tips and common mistakes
Tips
- Measure resting heart rate first thing in the morning, before coffee or movement, for consistency.
- Use the Karvonen numbers if you're fit — they track intensity better than percentage-of-max alone.
- You should be able to talk in the moderate zone and speak only in short phrases in the vigorous zone.
- Retest occasionally; your resting rate often drops as fitness improves, which shifts your zones.
Common mistakes to avoid
- Training by percentage of max HR without considering a very high or low resting rate.
- Relying on a wearable's default zones without checking them against your real resting rate.
- Pushing into peak zones for routine workouts — most training belongs in moderate or vigorous.
Heart Rate Calculator — frequently asked questions
What is a good resting heart rate?
For most adults, 60 to 100 bpm is normal, with well-trained athletes often in the 40s and 50s. A consistently very high resting rate is worth discussing with a doctor.
How is maximum heart rate calculated?
The most common estimate is 220 minus your age. The Tanaka formula (208 − 0.7 × age) is an alternative that tends to be more accurate for older adults.
What is the Karvonen formula?
It computes target heart rate as resting rate plus a percentage of the heart rate reserve (max minus resting). It personalizes zones for people whose resting rates differ from average.
What zone should I train in?
For general fitness, the American Heart Association suggests moderate (50–70% of max HR) most days, with vigorous sessions (70–85%) on some days if your health allows.
Why does my heart rate vary between the two methods?
The max-based method ignores your resting rate, while Karvonen builds it in. For example, a low resting rate produces lower Karvonen targets at the same percentage.
Can I use these zones with heart conditions?
Heart rate formulas are not validated for everyone on medication or with cardiac conditions. Ask your healthcare provider for personally appropriate intensity targets.