Heart Rate Training Zone Calculator
Target heart rate zones for cardio training.
Enter your values
Enter the age you are working with.
Enter the resting heart rate in bpm.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Max heart rate
- 185 bpm
- Zone 1 (50-60%) Warm-up
- 125-137 bpm
- Zone 2 (60-70%) Fat burn
- 137-149 bpm
- Zone 3 (70-80%) Aerobic
- 149-161 bpm
- Zone 4 (80-90%) Anaerobic
- 161-173 bpm
- Zone 5 (90-100%) Max effort
- 173-185 bpm
Quick answer
Target heart rate uses the Karvonen formula: ((max HR - resting HR) x intensity%) + resting HR.
target HR = ((220 - age - resting HR) x intensity%) + resting HR
At a glance
| What it does | Target heart rate zones for cardio training. |
|---|---|
| Category | Fitness |
| Inputs needed | Age, Resting heart rate |
| Main output | Max heart rate |
| Formula | target HR = ((220 - age - resting HR) x intensity%) + resting HR |
| Cost | Free — no sign-up, no download |
How to use the Heart Rate Training Zone Calculator
- 1Enter your age to estimate max heart rate (220 - age).
- 2Enter your resting heart rate, ideally measured first thing in the morning.
- 3Use the Karvonen formula zones to target the right intensity for warm-up, fat burn, aerobic or max effort training.
Inputs explained
- Age
- Enter the age you are working with.
- Resting heart rate(bpm)
- Enter the resting heart rate in bpm.
Worked example
Using the values the calculator loads with:
Inputs
- Age35
- Resting heart rate65 bpm
Results
- Max heart rate185 bpm
- Zone 1 (50-60%) Warm-up125-137 bpm
- Zone 2 (60-70%) Fat burn137-149 bpm
- Zone 3 (70-80%) Aerobic149-161 bpm
- Zone 4 (80-90%) Anaerobic161-173 bpm
- Zone 5 (90-100%) Max effort173-185 bpm
Frequently asked questions
Why use resting heart rate in the formula?
The Karvonen method accounts for individual fitness level via heart rate reserve, making it more accurate than max HR alone.
How do I measure resting heart rate?
Check your pulse for 60 seconds right after waking up, before getting out of bed, for several days and average it.
What do I need to enter into the Heart Rate Training Zone Calculator?
Just 2 values: age, resting heart rate. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Heart Rate Training Zone Calculator work out the answer?
Target heart rate uses the Karvonen formula: ((max HR - resting HR) x intensity%) + resting HR. It applies the formula target HR = ((220 - age - resting HR) x intensity%) + resting HR and shows the working so you can check each step by hand.
Is the Heart Rate Training Zone Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.