What maximum heart rate means
Your maximum heart rate (MHR) is the highest number of beats per minute your heart can reach during all-out effort. It’s a personal reference point for training smarter: from it you get your training zones, the heartbeat ranges where your body responds to exercise in different ways. Training in the wrong zone is why so many people work hard but improve slowly.
This calculator estimates your MHR and splits your effort into five zones. Everything runs in your browser — no data is sent or stored.
How to use the calculator
- Enter your age.
- If you know it, add your resting heart rate (measure it right after waking, lying down, before you get up). It’s optional, but it sharpens the result a lot.
- Pick the MHR formula and, if you entered a resting rate, the method used to build the zones.
The tool shows your MHR, the value from the other formula for comparison, and a table with the beat-per-minute range of every zone.
220 − age versus the Tanaka formula
The best-known formula is 220 − age. It’s easy to remember and good enough for most people, but it came from an informal observation in the 1970s and can be off by a fair margin for older adults.
The Tanaka formula (208 − 0.7 × age), published in 2001 from a meta-analysis, is considered more accurate, especially past 40. No formula is exact — these are population estimates with a spread of about ±10 to 12 beats. The truly reliable number comes from a supervised stress test.
Worked example
A 30-year-old:
- With
220 − 30, MHR is 190 bpm. - The aerobic zone (70-80%) runs from
190 × 0.70 = 133to190 × 0.80 = 152beats. - Training between 133 and 152 bpm keeps the effort in the range that builds cardiovascular fitness.
With Tanaka the same person gets 187 bpm — almost identical here; the gap grows with age.
The 5 training zones
| Zone | % of MHR | What it is for |
|---|---|---|
| Very light | 50-60% | Warm-up, recovery and cool-down |
| Fat burn | 60-70% | Base endurance; burns fat as fuel |
| Aerobic | 70-80% | Builds cardiovascular fitness and stamina |
| Anaerobic | 80-90% | Boosts speed and power in short efforts |
| Maximum | 90-100% | All-out effort; very short intervals only |
A balanced plan spends most of the time in the low and middle zones and saves the high ones for occasional sessions.
The Karvonen method
If you enter your resting heart rate, the calculator can use the Karvonen method, which is more personalized. Instead of applying the percentage straight to your MHR, it applies it to your heart rate reserve (MHR minus resting rate) and then adds your resting rate back:
Target HR = (MHR − resting HR) × % + resting HR
Because it accounts for how fit your heart is (a low resting rate signals good conditioning), the ranges it produces fit you better than a plain percentage of MHR.
Frequently asked questions
Which formula should I use?
For everyday use, 220 − age is plenty and easy to recall. If you’re over 40 or want something tighter, use Tanaka. And if you know your resting heart rate, switch on the Karvonen method — it’s the most personal of the three.
What’s the fat-burning zone?
It’s 60-70% of your MHR. At that moderate intensity your body draws a high share of its energy from fat. That said, for weight loss what matters is total calories burned: a harder workout burns more fat in absolute terms even if the percentage is lower.
Is 220 − age accurate?
No — it’s just an approximation. It can be off by ±10 to 12 beats from person to person, because genetics and fitness matter a lot. Treat it as a guide rather than a hard limit, and pay attention to how you feel while training.
Can I rely on these zones for training?
They’re a great starting guide, but only an informational estimate, not medical advice. Check with a healthcare professional before starting a plan, especially if you have a heart condition, take medication, or have been inactive for a while.