Heart Rate Zone Calculator
Calculate your target heart rate zones for fat burning, cardio, and peak performance. Based on age and max heart rate.
About this calculator
This tool builds your heart rate zones from your age and resting heart rate using the formula you choose: the classic 220 minus age, the Tanaka formula or the Gulati formula, which was developed for women. It then applies the Karvonen method to give five colour-coded zones.
Choosing the formula matters more than most people think. For a 30-year-old, the classic estimate is 190 and Tanaka is 187. For a 50-year-old woman, Gulati gives about 163, against 170 from the classic formula.
How to use it
- Enter your Age and Resting Heart Rate.
- Choose the Formula.
- Read the maximum heart rate, reserve and the five zones.
The three formulas
Classic: 220 − age. Tanaka: 208 − 0.7 × age. Gulati (women): 206 − 0.88 × age. Zones: Resting + Reserve × intensity, with Zone 1 at 50 to 60% up to Zone 5 at 90 to 100%.
Worked example
Age 30, resting 65, Tanaka
| Max heart rate | 187 bpm |
| Karvonen reserve | 122 bpm |
| Zone 2 Fat burning | 138 to 150 bpm |
| Zone 4 Anaerobic | 163 to 175 bpm |
| Zone 5 Peak | 175 to 187 bpm |
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
- Use Gulati if you are a woman, as the classic rule overestimates your maximum.
- Test your real maximum with a coach for high-intensity training.
- A resting rate that creeps up can signal fatigue or illness.
- Always warm up before reaching zone 4.
- Record your heart rate in your training log to see fitness changes.
Frequently asked questions
What is the Gulati formula?
206 minus 0.88 times age, developed from a study of women.
Which max heart rate formula should I use?
Tanaka for adults in general, Gulati for women, classic for a quick estimate.
What is the difference between zones 4 and 5?
Zone 4 is hard but sustainable for minutes; zone 5 is short bursts.
Do trained athletes have different zones?
They often have lower resting rates and higher reserves.
Is my wearable accurate?
Generally within 5 beats at rest and steady effort.
Should I always train in the same zone?
No. Mix easy and hard sessions.