Heart Rate Zone Calculator

Five-zone training planner

See every heart-rate zone at a glance

Pick a method, enter only the values it needs, and get five color-coded ranges with the formula kept in view.

Results

Your five training zones

Example

Maximum used190bpm

MethodKarvonen / heart-rate reserveEntered maximum

Heart-rate reserve130 bpmmaximum minus rest

Lower relative intensityHigher relative intensity

Z150–60%
Z260–70%
Z370–80%
Z480–90%
Z590–100%

Z1
Zone 1Very light effort cue
Intensity50–60%
Target range125–138bpm
Z2
Zone 2Light effort cue
Intensity60–70%
Target range138–151bpm
Z3
Zone 3Moderate effort cue
Intensity70–80%
Target range151–164bpm
Z4
Zone 4Hard effort cue
Intensity80–90%
Target range164–177bpm
Z5
Zone 5Very hard effort cue
Intensity90–100%
Target range177–190bpm

Adjacent rows share a boundary. The effort words are orientation cues—not physiological thresholds or a workout prescription.

Planning estimate only

Age predictions and percentage bands vary by person. Medicines, health conditions, heat, fatigue, hydration, and sensor error can change heart-rate response; follow a clinician-supervised target when one has been prescribed.

Transparent five-band heart-rate planner

Build Heart-Rate Zones from a Declared Maximum and Method

Choose either percentage of maximum heart rate or heart-rate reserve, then choose an entered maximum or the Tanaka age prediction. The calculator displays five equal mathematical bands from 50% through 100%. Those bands are a planning convention—not universal physiological thresholds, clinical targets, or named benefit zones.

Side-by-side guide · Transparent five-band heart-rate planner

Decide Whether Resting Heart Rate Belongs in the Method

Zone bands: 50–60, 60–70, 70–80, 80–90, 90–100%
HRR equation: Rest + intensity × (maximum − rest)
Maximum source: Entered value or Tanaka age estimate

Percentage of maximum
Each boundary is the selected fraction multiplied by maximum heart rate. Resting rate is intentionally omitted, so adding it later would create a hybrid formula.
Heart-rate reserve
Subtract rest from maximum, multiply that reserve by the boundary fraction, and add rest back. The entered resting rate must be below the resolved maximum.
Clinically tested target
A target from supervised testing or cardiac rehabilitation is not merely a third calculator mode. It can incorporate conditions and medicines that population arithmetic cannot model.

Build Heart-Rate Zones from a Declared Maximum and Method: Choose either percentage of maximum heart rate or heart-rate reserve, then choose an entered maximum or the Tanaka age prediction. The calculator displays five equal mathematical bands from 50% through 100%. Those bands are a planning convention—not universal physiological thresholds, clinical targets, or named benefit zones.

Decide Whether Resting Heart Rate Belongs in the Method

Percentage of maximum

Each boundary is the selected fraction multiplied by maximum heart rate. Resting rate is intentionally omitted, so adding it later would create a hybrid formula.

Heart-rate reserve

Subtract rest from maximum, multiply that reserve by the boundary fraction, and add rest back. The entered resting rate must be below the resolved maximum.

Clinically tested target

A target from supervised testing or cardiac rehabilitation is not merely a third calculator mode. It can incorporate conditions and medicines that population arithmetic cannot model.

Choose and Label the Maximum-Heart-Rate Source

Use an appropriate entered maximum
Enter a value only when its protocol and measurement are credible. An isolated wearable spike may be artifact rather than a demonstrated maximum.
Or use an age prediction
The maximum heart-rate calculator applies 208 − 0.7 × age for adults 18–81 and preserves its population scatter warning.
Measure rest consistently for HRR
Use a representative quiet resting value measured under a repeatable protocol, not a reading taken immediately after caffeine, activity, stress, or illness.

Audit Two Complete Heart-Rate Zone Examples

The calculator keeps the five percentage bands fixed while the selected method changes how each boundary becomes bpm. These examples use the same arithmetic shown in the result panel and round only the displayed endpoints.

Age 40 · percentage of maximum

Tanaka estimates HRmax as 208 − 0.7 × 40 = 180 bpm. Multiplying 180 by each boundary gives Zone 1 at 90–108, Zone 2 at 108–126, Zone 3 at 126–144, Zone 4 at 144–162, and Zone 5 at 162–180 bpm.

Maximum 190 · rest 60 · Karvonen

Heart-rate reserve is 190 − 60 = 130 bpm. The first lower boundary is 60 + 0.50 × 130 = 125 bpm; the full table is 125–138, 138–151, 151–164, 164–177, and 177–190 bpm.

Why the two tables differ

Percentage of maximum measures every boundary from zero. Karvonen first scales the difference between maximum and rest, then adds rest back. Do not mix one method's lower boundary with the other method's upper boundary.

Read Shared Boundaries Without Inventing Training Benefits

The five rows share endpoints: the 60% boundary closes Zone 1 and opens Zone 2, for example. Raw adjacent endpoints are identical before display rounding. The labels remain Zone 1 through Zone 5 because names such as “fat burning,” “anaerobic,” or “peak” imply benefits and thresholds that differ across sports, protocols, and individuals.

The American Heart Association describes about 50–70% of maximum as a general moderate range and 70–85% as vigorous. Those broad guides do not align one-to-one with five equal 10-point bands. A VO2 max field estimate also cannot identify ventilatory or lactate thresholds, so do not use it to rename these rows.

Override the Zone Table When Health Context Demands It

Beta blockers and other rate-altering medicines can make predicted-max zones inappropriate. Follow the qualified clinician or rehabilitation program that knows the medication context.
Heart disease, rhythm disorders, autonomic dysfunction, pregnancy, recent illness, heat, altitude, and dehydration can alter response and safe exercise decisions.
Stop and seek appropriate help for chest pain, fainting, severe breathlessness, or other concerning symptoms instead of trying to remain within a calculated band.
Poor sleep can change perceived effort and recovery, but the sleep schedule planner is not a heart-rate correction factor and these zones do not diagnose sleep-related risk.

Use Repeatable Zones for Session Description, Not Clearance

For training logs, preserve the maximum source, maximum value, resting protocol and value when applicable, method, calculation date, and unrounded boundaries. Recalculate when medication, health, measured maximum, or representative resting rate changes. Comparing sessions with different zone definitions can create a false trend even if the heart-rate recordings are accurate.

Heart rate can lag sudden workload changes and is influenced by temperature, fatigue, hydration, emotion, and sensor placement. Pair it with pace, power, perceived exertion, symptoms, and the purpose of the session. This calculator cannot diagnose cardiovascular disease, locate metabolic thresholds, prescribe a workout, or certify that an intensity is safe. Its narrow role is to make two common percentage methods visible and reproducible.

Important limitations

Heart Rate Zone Calculator returns maximum heart rate used, maximum source, zone method, and zone 1 lower boundary only for the stated population, method, and source period. It is an informational calculation rather than a diagnosis, treatment plan, dosing instruction, exposure assessment, or individualized clinical recommendation.

Review the stated scope, calculation method, assumptions, supported inputs, and effective dates, and obtain qualified advice before using a high-stakes result.

This formula passed its registered engineering tests and is published under an explicit site-owner policy authorization. No independent expert, QA, editorial, legal, or third-party review is claimed. Verify consequential results with a qualified professional.

This subject may affect health, finance, tax, legal, or other consequential decisions. It has not received an independent domain-expert review; consult a qualified professional before relying on it.

Transparent five-band heart-rate planner

Build Heart-Rate Zones from a Declared Maximum and Method

Side-by-side guide · Transparent five-band heart-rate planner

Decide Whether Resting Heart Rate Belongs in the Method

Zone bands: 50–60, 60–70, 70–80, 80–90, 90–100%
HRR equation: Rest + intensity × (maximum − rest)
Maximum source: Entered value or Tanaka age estimate

Percentage of maximum
Each boundary is the selected fraction multiplied by maximum heart rate. Resting rate is intentionally omitted, so adding it later would create a hybrid formula.
Heart-rate reserve
Subtract rest from maximum, multiply that reserve by the boundary fraction, and add rest back. The entered resting rate must be below the resolved maximum.
Clinically tested target
A target from supervised testing or cardiac rehabilitation is not merely a third calculator mode. It can incorporate conditions and medicines that population arithmetic cannot model.

Decide Whether Resting Heart Rate Belongs in the Method

Percentage of maximum

Each boundary is the selected fraction multiplied by maximum heart rate. Resting rate is intentionally omitted, so adding it later would create a hybrid formula.

Heart-rate reserve

Subtract rest from maximum, multiply that reserve by the boundary fraction, and add rest back. The entered resting rate must be below the resolved maximum.

Clinically tested target

A target from supervised testing or cardiac rehabilitation is not merely a third calculator mode. It can incorporate conditions and medicines that population arithmetic cannot model.

Choose and Label the Maximum-Heart-Rate Source

Use an appropriate entered maximum
Enter a value only when its protocol and measurement are credible. An isolated wearable spike may be artifact rather than a demonstrated maximum.
Or use an age prediction
The maximum heart-rate calculator applies 208 − 0.7 × age for adults 18–81 and preserves its population scatter warning.
Measure rest consistently for HRR
Use a representative quiet resting value measured under a repeatable protocol, not a reading taken immediately after caffeine, activity, stress, or illness.

Audit Two Complete Heart-Rate Zone Examples

Age 40 · percentage of maximum

Maximum 190 · rest 60 · Karvonen

Heart-rate reserve is 190 − 60 = 130 bpm. The first lower boundary is 60 + 0.50 × 130 = 125 bpm; the full table is 125–138, 138–151, 151–164, 164–177, and 177–190 bpm.

Why the two tables differ

Read Shared Boundaries Without Inventing Training Benefits

Override the Zone Table When Health Context Demands It

Beta blockers and other rate-altering medicines can make predicted-max zones inappropriate. Follow the qualified clinician or rehabilitation program that knows the medication context.
Heart disease, rhythm disorders, autonomic dysfunction, pregnancy, recent illness, heat, altitude, and dehydration can alter response and safe exercise decisions.
Stop and seek appropriate help for chest pain, fainting, severe breathlessness, or other concerning symptoms instead of trying to remain within a calculated band.
Poor sleep can change perceived effort and recovery, but the sleep schedule planner is not a heart-rate correction factor and these zones do not diagnose sleep-related risk.

Set up your calculation

Your five training zones

Percentage of maximum

Heart-rate reserve

Clinically tested target

Decide Whether Resting Heart Rate Belongs in the Method

Percentage of maximum

Heart-rate reserve

Clinically tested target

Choose and Label the Maximum-Heart-Rate Source

Audit Two Complete Heart-Rate Zone Examples

Age 40 · percentage of maximum

Maximum 190 · rest 60 · Karvonen

Why the two tables differ

Read Shared Boundaries Without Inventing Training Benefits

Override the Zone Table When Health Context Demands It

Use Repeatable Zones for Session Description, Not Clearance

Important limitations

Set up your calculation

Your five training zones

Percentage of maximum

Heart-rate reserve

Clinically tested target

Decide Whether Resting Heart Rate Belongs in the Method

Percentage of maximum

Heart-rate reserve

Clinically tested target

Choose and Label the Maximum-Heart-Rate Source

Audit Two Complete Heart-Rate Zone Examples

Age 40 · percentage of maximum

Maximum 190 · rest 60 · Karvonen

Why the two tables differ

Read Shared Boundaries Without Inventing Training Benefits

Override the Zone Table When Health Context Demands It

Use Repeatable Zones for Session Description, Not Clearance