Heart Rate Zone Calculator

Calculate your 5 heart rate training zones using Karvonen or percentage method. Optimise workouts for fat burn, endurance, and VO2 max.

Free to use. Runs in your browser.

Heart rate training zones divide effort into 5 intensity bands. Zone 1 (50 to 60%) = recovery; Zone 2 (60 to 70%) = fat burn / aerobic base; Zone 3 (70 to 80%) = cardiovascular fitness; Zone 4 (80 to 90%) = lactate threshold; Zone 5 (90 to 100%) = VO2 max. Max HR is estimated via the Tanaka formula: 208 − (0.7 × age). The Karvonen method uses your resting HR for more accurate personal zones.

Enter your age and resting heart rate below to see all 5 training zones in bpm.

Age

Resting Heart Rate (bpm)

Method

Custom Max HR (optional)

Educational Estimates Only: These calculations are approximations based on population-level formulas and may not accurately reflect your individual health status. Body composition varies significantly due to factors like muscle mass, bone density, hydration, and ethnicity. This is not medical advice. Always consult a qualified healthcare provider for personalized assessment, diagnosis, or treatment decisions.

Methodology and sources

Formula or method

Estimates maximum heart rate with the Tanaka equation, then calculates training zones either as percentages of max heart rate or with the Karvonen heart-rate-reserve method.

Basis and assumptions

Tanaka max HR estimate: 208 - (0.7 x age).
Karvonen method: target HR = ((max HR - resting HR) x intensity) + resting HR.
Zone bands use the percentages displayed in the tool, from recovery to VO2 max.
Formula zones are estimates and can differ from lab or supervised stress-test results.

What this tool does not decide

Whether a heart-rate zone is safe for you. Consult a GP, cardiologist, exercise physiologist, or healthcare professional.
Training advice for chest pain, arrhythmias, pregnancy, beta-blockers, stimulant medication, or cardiac rehabilitation.

Sources

Tanaka, Monahan & Seals (2001), J Am Coll Cardiol 37:153-156
Karvonen heart-rate-reserve method, as named in this tool

Last checked: 2026-06-05

Why Training by Heart Rate Beats Training by Feel

"Go hard" isn't a training plan. Your body responds differently to different intensities, and the only way to ensure you're in the right zone is to measure it. A heart rate monitor turns guesswork into precision.

Each of the 5 heart rate zones triggers specific physiological adaptations, from fat burning and endurance building in the lower zones to lactate threshold and VO2 max improvements in the higher zones. Training in the wrong zone means you're working hard but not getting the results you want.

The 5 Heart Rate Zones Explained

Zone	% Max HR	Feels Like	What It Trains	How Long
Zone 1: Recovery	50 to 60%	Very easy, can chat freely	Active recovery, warm-up	30 to 60 min
Zone 2: Aerobic Base	60 to 70%	Comfortable, can hold conversation	Fat burning, endurance foundation	45 to 120 min
Zone 3: Tempo	70 to 80%	Moderate, short sentences only	Aerobic capacity, efficiency	20 to 40 min
Zone 4: Threshold	80 to 90%	Hard, can barely talk	Lactate threshold, race speed	10 to 20 min intervals
Zone 5: VO2 Max	90 to 100%	Maximum effort, can't talk	Max oxygen uptake, sprint power	30 sec to 3 min intervals

What this means for you: Most recreational athletes spend too much time in Zone 3, the "no man's land" that's too hard for recovery but too easy for real improvement. Elite athletes spend 80% of their training in Zones 1 to 2 and 20% in Zones 4 to 5. This "polarised training" approach produces the best long-term results.

Karvonen vs Percentage Method: Which Is More Accurate?

The percentage method calculates zones as simple percentages of your max heart rate. It's easy but ignores your fitness level.

The Karvonen method uses your heart rate reserve (max HR minus resting HR), which accounts for individual fitness. A fit person with a resting HR of 50 bpm gets different zones than an unfit person with a resting HR of 80 bpm, even if they're the same age.

Use Karvonen if you know your resting heart rate (measure it first thing in the morning). Use the percentage method only if you don't have resting HR data. The Karvonen zones are more personalised and more accurate, especially for Zone 2 training.

How to Find Your True Max Heart Rate

The formula 220 minus age is popular but inaccurate, it can be off by 10 to 20 bpm. The Tanaka formula (208 − 0.7 x age) is better but still an estimate. The only reliable way to find your true max HR is a field test:

Warm up for 10 minutes at an easy pace
Find a hill that takes 2 to 3 minutes to climb (or use a treadmill incline)
Run up at a hard effort, not quite a sprint, but close to maximum
Jog back down and repeat 3 times, going harder each time
On the third repeat, sprint the last 30 seconds all-out
The highest heart rate recorded during the test is your max HR

Warning: Only attempt this if you're healthy and have been exercising regularly. If you have any heart conditions, get a supervised stress test from a cardiologist instead.

Resting Heart Rate: What It Tells You

Resting HR (bpm)	Fitness Level	Typical For
Below 50	Elite	Endurance athletes, professional cyclists
50-59	Excellent	Regular runners, swimmers, serious gym-goers
60-69	Good	Active adults who exercise 3-4 times per week
70-79	Average	Moderately active adults
80-89	Below average	Sedentary adults, may indicate poor fitness
90+	See a doctor	May indicate stress, dehydration, or underlying condition

Measure your resting heart rate first thing in the morning, before getting out of bed. Track it weekly, a gradually declining RHR over months is one of the best signs that your fitness is improving. A sudden spike of 10+ bpm can indicate illness, overtraining, or stress.

Worked Karvonen Example

The Karvonen method uses heart-rate reserve, so it changes when resting heart rate changes. For a 40-year-old with an estimated max HR of 180 bpm and resting HR of 60 bpm, heart-rate reserve is 120 bpm.

Zone	Calculation	Example range
Zone 2 lower edge	120 x 60 percent + 60	132 bpm
Zone 2 upper edge	120 x 70 percent + 60	144 bpm
Zone 4 lower edge	120 x 80 percent + 60	156 bpm

If resting heart rate falls to 50 bpm after training, the reserve becomes larger and the same zone percentages produce different targets. That is why updating resting HR every few weeks can be useful.

Cross-Check Zones With Effort

Zone 1 to 2

Breathing is controlled and conversation is possible. These zones should feel sustainable and are useful for warm-ups, recovery, and aerobic base work.

Zone 3

Conversation becomes shorter. This can be useful for tempo work, but it can also accumulate fatigue if every session lands here.

Zone 4

Speech is limited to a few words. Sessions in this range should be planned and followed by recovery.

Zone 5

This is near-maximal work. Use short intervals only if you are already trained and have no medical reason to avoid hard exercise.

When Heart Rate Formulas Need Extra Care

Beta-blockers and some other medicines can lower heart-rate response, making formula zones unsuitable.
Heat, dehydration, caffeine, poor sleep, illness, and stress can raise heart rate at the same pace.
Chest pain, faintness, irregular heartbeat, or unusual breathlessness during training should be assessed by a healthcare professional.
If you are returning after illness, pregnancy, surgery, or cardiac rehabilitation, use clinician-led targets rather than calculator zones.

Heart Rate Zone Review Checklist

Zones work best when formula output, perceived effort, and recovery all point in the same direction.

Update resting heart rate when your fitness changes.
Use talk-test feedback when the monitor reading looks unusual.
Keep easy days genuinely easy so higher-zone work has room to be effective.

Related Fitness Tools

Target Heart RateFind your exercise heart rate range VO2 Max CalculatorEstimate your aerobic fitness level Pace CalculatorCalculate your running pace Calories BurnedHow many calories your workout burns TDEE CalculatorFind your total daily calorie needs BMR CalculatorCalculate your resting metabolic rate

Part of a workflow

Health & Fitness Workflow

Body baseline → Calories → Nutrition → Training → Progress. 13 tools free.

How to use this tool

Enter your age

Enter resting heart rate and choose a zone method

Calculate your 5 training zones in bpm

Common uses

Setting heart rate targets for cardio workouts
Finding the right intensity for fat-burning exercise
Training for a marathon, triathlon, or cycling event
Monitoring intensity during HIIT sessions
Building an aerobic base with Zone 2 training

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Frequently Asked Questions

How is max heart rate calculated?

This calculator uses the Tanaka formula: 208 − (0.7 x age), which is more accurate than the popular 220 − age formula. For a 40-year-old, both give 180 bpm, but they diverge at other ages. You can also enter a known max HR from a field test or stress test for the most accurate zones.

What are heart rate zones?

Heart rate zones divide your effort into 5 intensity levels, each targeting different physiological adaptations. Zone 1 (50 to 60%) is recovery. Zone 2 (60 to 70%) builds aerobic base and burns fat. Zone 3 (70 to 80%) improves cardiovascular efficiency. Zone 4 (80 to 90%) raises lactate threshold. Zone 5 (90 to 100%) develops VO2 max.

What is the Karvonen method?

The Karvonen formula uses your heart rate reserve (max HR minus resting HR) to personalise zones: Target = ((Max HR − Resting HR) × %) + Resting HR. A fit person with a resting HR of 50 gets different zones than someone at 80 bpm, even if they're the same age. It's more accurate than simple percentages of max HR.

Which zone is best for weight loss?

Zone 2 (60 to 70%) burns the highest percentage of calories from fat. But higher zones burn more total calories per minute. For weight loss, total calorie deficit matters most, so a mix of Zone 2 base training and Zone 4 to 5 intervals is the most effective strategy. Zone 2 also builds the aerobic base that makes harder sessions possible.

How do I find my resting heart rate?

Measure your pulse first thing in the morning, before getting out of bed. Count beats for 60 seconds on 3 consecutive mornings and average the results. Don't measure after caffeine, alcohol, or a bad night's sleep. Most fitness watches also track this automatically. A lower resting HR generally indicates better cardiovascular fitness.

Why is Zone 2 training so popular?

Zone 2 training builds mitochondrial density, your cells' ability to produce energy from fat. It's where elite endurance athletes spend 80% of their training time. It feels easy (you can hold a full conversation), but the adaptations are profound: better fat oxidation, improved endurance, lower resting heart rate, and a stronger aerobic foundation for harder work.

How long should I train in each zone?

Zone 1: 20 to 60 min (warm-up/cool-down). Zone 2: 45 to 120 min (long aerobic sessions). Zone 3: 20 to 40 min (tempo runs). Zone 4: 10 to 20 min total (threshold intervals, e.g., 4x4 min). Zone 5: 3 to 10 min total (short intervals, e.g., 6x30 sec). Never spend an entire session in Zone 5. Most sessions should be Zone 1 to 2.

Does medication affect my heart rate zones?

Yes. Beta-blockers lower both resting and max heart rate significantly, making standard formulas unreliable. Stimulants, decongestants, and some antidepressants can raise resting HR. If you take any heart-affecting medication, ask your doctor for a supervised stress test to find your true max HR and zones.

Why are my zones different from my fitness watch?

Fitness watches often use the simpler 220 − age formula and the percentage method (not Karvonen). This calculator uses the more accurate Tanaka formula and optionally the Karvonen method, which accounts for your resting HR. The difference can be 10 to 15 bpm per zone, which is enough to change your training focus entirely.

What is the 'talk test' for heart rate zones?

Zone 1 to 2: can hold a full conversation. Zone 3: can speak in short sentences. Zone 4: can barely get a few words out. Zone 5: can't talk at all. The talk test is surprisingly accurate and useful when you don't have a heart rate monitor, research shows it correlates well with lactate threshold.

Can I train in Zone 5 every day?

No. Zone 5 creates significant physiological stress and requires 48 to 72 hours of recovery. Training in Zone 5 more than 2 to 3 times per week leads to overtraining, elevated resting heart rate, poor sleep, and decreased performance. Most of your training (80%) should be in Zones 1 to 2, with only 20% in Zones 4 to 5.

What is heart rate variability (HRV)?

HRV measures the variation in time between heartbeats. Higher HRV generally indicates better fitness and recovery. It's different from heart rate zones but complementary, low HRV in the morning suggests you need a recovery day (Zone 1 to 2), while high HRV means you're ready for a harder session (Zone 4 to 5). Most modern fitness watches track HRV.

Results are for general informational purposes only and should be checked before use. They are not professional advice. See our Disclaimer and Terms of Service.