Heart Rate Zone Calculator
Calculate your target heart rate zones for fat burn, cardio, and peak training based on age and max HR.
About Heart Rate Zones
Uses the Karvonen formula (Heart Rate Reserve) to calculate personalized zones based on your age and resting heart rate.
About this calculator
Heart Rate Zone Calculator splits your heart rate range into five training zones using the Tanaka formula for maximum heart rate, which is more accurate than 220 minus age for adults. Enter your age and resting heart rate and you get a zone chart with a description of what each zone trains.
Each zone has a purpose: recovery, aerobic base, steady aerobic work, threshold and maximum effort. Use the table to set the target on your watch or treadmill.
How to use it
- Enter your Age.
- Enter your Resting Heart Rate.
- Press Calculate Zones.
- Read each zone's beats-per-minute range.
Tanaka formula and zones
Max HR = 208 − 0.7 × age (Tanaka). Reserve = Max − Resting. Zones are percentages of the reserve added to the resting rate: 50 to 60, 60 to 70, 70 to 80, 80 to 90 and 90 to 100%.
Worked example
Age 30, resting rate 65
| Max heart rate | 187 bpm |
| Zone 1 Warm up | 126 to 138 |
| Zone 2 Fat burn | 138 to 150 |
| Zone 3 Aerobic | 150 to 163 |
| Zone 4 Anaerobic | 163 to 175 |
| Zone 5 Max effort | 175 to 187 |
This tool gives general information, not medical advice. Talk to a doctor or dietitian before making changes to your diet, exercise or medication.
Tips and common mistakes
- The Tanaka formula suits adults of all ages better than the 220 rule.
- Use zone 2 for long, easy sessions, up to 80% of your weekly training.
- Wrist heart-rate sensors lag during intervals. A chest strap is more accurate.
- Update your resting rate every month as fitness improves.
- Heat, stress and poor sleep raise heart rate at the same effort.
Frequently asked questions
What is the Tanaka formula?
208 minus 0.7 times age, a more accurate estimate of maximum heart rate than 220 minus age.
What are the five heart rate zones?
Warm-up, fat burn, aerobic, anaerobic and maximum effort.
What is zone 2 training?
Easy to moderate effort where you can hold a conversation.
How do I find my resting heart rate?
Count your pulse for a minute when you wake, before getting up.
Can I trust my watch?
Wrist sensors are good at steady effort and less so during intervals.
Do zones change with age?
Yes, maximum heart rate falls with age.