Heart Rate Zone Calculator
Enter your age and resting heart rate to get your max heart rate, your target heart rate and five training zones in beats per minute.
Count your pulse sitting quietly, ideally just after waking.
From a hard, safe test or race. It replaces the formula.
Any share of max, reserve or LTHR (by the method above).
Friel's test: your average heart rate over the last 20 minutes of a solo 30-minute all-out run or ride.
Your heart rate zones
| Zone | bpm | Per 10 s | Per 15 s |
|---|
Per 10 s and per 15 s are the beats to count for a quick manual pulse check at the wrist or neck.
Moderate and vigorous exercise ranges
| Intensity | Share | By % of max | By reserve |
|---|
American Heart Association guidance: moderate exercise at 50–70% and vigorous at 70–85% of your max heart rate (heart.org). The "by reserve" column applies the same shares with the Karvonen method.
Max heart rate by every formula
| Formula | Sum | Your max |
|---|
Real max heart rates vary by 10 bpm or more either side of any formula.
How your heart rate zones are worked out
Estimate your max, find the range you work in, then take a share of it for each zone.
- 1
Max heart rate
220 − 35= 185 bpm
- 2
Heart rate reserve
185 − 65= 120 bpm
- 3
Zone 3, tempo
65 + 120 × 70%= 149 bpmto 161 bpm
- 4
Pulse check
149 ÷ 4= 37 in 15 s= 25 in 10 s
Read more: the formulas, a worked example, every zone and the AHA ranges
Heart rate zones split the range between easy and flat-out effort into bands, so you can train at the right effort for what you want: recovery, endurance, speed or top-end fitness. This is general fitness guidance, not medical advice. If you have a heart condition, take medicine that changes your heart rate (such as beta blockers), are pregnant or are new to exercise, check with a doctor first.
The formula
max heart rate = 220 − age (or Tanaka: 208 − 0.7 × age)
heart rate reserve = max − resting
Karvonen target = resting + reserve × intensity
% of max target = max × intensity
LTHR zone = LTHR × zone share
beats per 15 s = bpm ÷ 4 · per 10 s = bpm ÷ 6
Worked example
You are 35 with a resting heart rate of 65 bpm. Your estimated max is 220 − 35 = 185 bpm, so your heart rate reserve is 185 − 65 = 120 bpm. Zone 3 (tempo) is 70–80% of the reserve: 65 + 120 × 0.7 = 149 bpm to 65 + 120 × 0.8 = 161 bpm. To check 149 bpm by hand, count 149 ÷ 4 = 37.25, about 37 beats in 15 seconds, or 149 ÷ 6 ≈ 25 in 10 seconds.
| Zone | Share | Heart rate reserve | % of max |
|---|---|---|---|
| 1 Recovery | 50–60% | 125–137 | 93–111 |
| 2 Aerobic / fat burn | 60–70% | 137–149 | 111–130 |
| 3 Tempo | 70–80% | 149–161 | 130–148 |
| 4 Threshold | 80–90% | 161–173 | 148–167 |
| 5 VO2 max | 90–100% | 173–185 | 167–185 |
By the AHA ranges (shares of max), moderate exercise for this person is 185 × 0.5 = 92.5 to 185 × 0.7 = 129.5, about 93–130 bpm, and vigorous exercise is 129.5 to 185 × 0.85 = 157.25, about 130–157 bpm.
Max heart rate formulas
- 220 − age (Fox): the classic rule of thumb used by the AHA. At 35: 185.
- Tanaka: 208 − 0.7 × age, from a large review of studies. At 35: 183.5.
- Gellish: 207 − 0.7 × age. At 35: 182.5.
- Gulati: 206 − 0.88 × age, made from women's exercise tests. At 35: 175.2.
- HUNT (Nes): 211 − 0.64 × age, from a large Norwegian study of healthy adults. At 35: 188.6.
Three ways to set zones
- % of max (Polar, Garmin default): each zone is a plain share of your max heart rate, 50–60%, 60–70% and so on. Needs only your age.
- Heart rate reserve (Karvonen): shares of the gap between resting and max, added to your resting rate. It adjusts for fitness, because a fitter heart rests lower.
- Lactate threshold (Joe Friel): shares of the heart rate you can hold for about an hour flat out. Running zones start at 85%, 90%, 95%, 100%, 103% and 106% of LTHR; cycling zones at 81%, 90%, 94%, 100%, 103% and 106%. If you leave LTHR blank, the calculator uses a rough 88% of max, which is only a starting point; a field test is far better.
Heart rate shifts with heat, dehydration, caffeine, stress, poor sleep and illness, and wrist sensors can be off during intervals. Use zones as a guide alongside how hard the effort feels. Stop and get help if you feel chest pain, faintness or unusual breathlessness.
Common questions
How do I work out my target heart rate?
First estimate your max heart rate. The classic sum is 220 minus your age, so 185 bpm at 35. Then take a share of it: the American Heart Association suggests 50–70% of max for moderate exercise (93–130 bpm at 35) and 70–85% for vigorous exercise (130–157 bpm). The calculator also gives five training zones.
What is the Karvonen formula?
It uses your heart rate reserve, which is max heart rate minus resting heart rate. Target = resting + reserve × intensity. At 35 with a resting rate of 65, the reserve is 185 − 65 = 120, so 70% is 65 + 120 × 0.7 = 149 bpm. It gives higher, more personal numbers than a plain share of max, especially for fit people.
Which max heart rate formula is most accurate?
No formula fits everyone; real max heart rates vary by 10 bpm or more either side. 220 − age is the best known. Tanaka (208 − 0.7 × age) was built from a much larger set of studies and reads higher for older people. Gulati (206 − 0.88 × age) was made for women. A measured max from a hard, safe test beats any formula.
What heart rate is zone 2?
Zone 2 is 60–70% of your max heart rate, or of your heart rate reserve with the Karvonen method. At 35 with a resting rate of 65, that is 111–130 bpm by % of max, or 137–149 bpm by heart rate reserve. It is easy, chatty effort that builds endurance.
How do I check my pulse during exercise?
Press two fingers on the inside of your wrist or the side of your neck and count the beats for 15 seconds, then multiply by 4. Or count for 10 seconds and multiply by 6. The table shows the counts for each zone, so a 149 bpm target is about 37 beats in 15 seconds.
What is a normal resting heart rate?
The American Heart Association gives 60–100 beats per minute as normal for adults. Fit people and endurance athletes often sit lower, sometimes in the 40s or 50s. Measure it lying or sitting quietly, ideally just after waking. If yours is often outside the normal range or you feel unwell, talk to a doctor.
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