2026-08-07 10 min

Target Heart Rate Calculator

Estimate MHR with Fox and Tanaka formulas, then find Karvonen target zones, fat-burn, cardio, and peak bands plus the simple 50–85% of MHR range.

Calculator

Your Numbers

Ageyears (10–100)

Resting HRbpm (30–120)

Method & Goal

MHR Method

Training Goal

Intensity Low%

Intensity High%

Results update automatically

Results update live as you type

Status:MHR 190 bpmTarget 140–153 bpmHRR 125 bpm

Target Heart Rate Summary

MHR (Fox 220 − age)190 bpm

MHR (Tanaka)187 bpm

Selected MHR (Fox)190 bpm

Heart Rate Reserve125 bpm

Target Zone (60–70%)140–153 bpm

Simple 50–85% MHR95–162 bpm

Karvonen Zone Table (50–100%)

Zone	Intensity	Target (bpm)
Zone 1 (Very light)	50–60%	128 – 140
Zone 2 (Light)	60–70%	140 – 153
Zone 3 (Moderate)	70–80%	153 – 165
Zone 4 (Hard)	80–90%	165 – 178
Zone 5 (Maximal)	90–100%	178 – 190
Selected	60–70%	140 – 153 bpm

Training Bands

Fat-burn (60–70%):140–153 bpm

Cardio (70–80%):153–165 bpm

Peak (80–90%):165–178 bpm

Results

Normal

Max Heart Rate (MHR)

190 bpmbpm

Fox 220 − age

Heart Rate Reserve (HRR)

125 bpmbpm

MHR − resting HR, the Karvonen range

Target Zone Low

140 bpmbpm

Karvonen at 60% intensity

Target Zone High

153 bpmbpm

Karvonen at 70% intensity

Fat-Burn Band (60–70%)

140–153 bpmbpm

Zone 2 light intensity, conversational pace

Cardio Band (70–80%)

153–165 bpmbpm

Zone 3 moderate intensity, aerobic power

Peak Band (80–90%)

165–178 bpmbpm

Zone 4 hard intensity, short intervals only

%MHR Band (50–85%)

95–162 bpmbpm

Simple MHR × % without resting HR

Age-predicted MHR is a population estimate (typically ±10–12 bpm), so treat zones as starting bands. Confirm with the talk test, and get medical clearance before vigorous Zones 4–5 if you have cardiac risk factors or have been inactive.

Visualizations

Karvonen Zones (midpoint bpm)

134 bpmZone 1

146 bpmZone 2

159 bpmZone 3

171 bpmZone 4

184 bpmZone 5

Karvonen HR vs Intensity (50–95%)

Target High Within Max

153bpm

65190

Position of Target in HRR

Target high70%

Target High vs MHR

Target high153 bpm

Formula

Maximum heart rate is estimated from age with Fox or Tanaka. Subtracting resting HR gives heart rate reserve (HRR). The Karvonen method then scales HRR by the chosen intensity and adds resting HR back, personalizing every zone. The simple %MHR band skips resting HR for a quick check.

MHR (Fox) = 220 − age; MHR (Tanaka) = 208 − 0.7 × age; Target = RHR + (MHR − RHR) × intensity%

Alternative Form

Simple band: Target = MHR × intensity% (50–85% for general health when RHR is unknown)

Variables

Symbol	Name	Unit	Description
A	Age	years	Chronological age used for MHR estimation
MHR	Maximum heart rate	bpm	220 − age (Fox) or 208 − 0.7 × age (Tanaka)
RHR	Resting heart rate	bpm	Morning resting beats per minute
HRR	Heart rate reserve	bpm	MHR − RHR, the Karvonen range
i	Intensity	%	Fraction of HRR, e.g. 0.60–0.70 for fat-burn
T	Target HR	bpm	RHR + HRR × i at the chosen intensity
S	Simple %MHR target	bpm	MHR × i without resting HR

Explanation

Age sets the ceiling, resting rate sets the floor, and intensity picks the height between them. Two people with the same age but different resting rates get different Karvonen targets, which is why Karvonen beats plain MHR × % for most adults.

Derivation

MHR (Fox) = 220 − age. MHR (Tanaka) = 208 − 0.7 × age. HRR = MHR − RHR. Target(low) = RHR + HRR × intensityLow%. Target(high) = RHR + HRR × intensityHigh%. Zone k = RHR + HRR × [pctLow_k, pctHigh_k] for 50–60/60–70/70–80/80–90/90–100%. Simple band = [MHR × 50%, MHR × 85%].

Step-by-Step Calculation

Follow each step to understand how the result is calculated from your inputs.

Step 1

Estimate MHR with the Fox formula.

MHR (Fox) = 220 − age

Age:30 years

Intermediate: 220 − 30

Result: MHR (Fox) = 190 bpm

Step 2

Estimate MHR with the Tanaka formula and pick the selected method.

MHR (Tanaka) = 208 − 0.7 × age

Age:30 years

Method:Fox

Intermediate: 208 − 0.7 × 30 = 187 bpm

Result: Selected MHR = 190 bpm (Fox)

Step 3

Subtract resting HR to get heart rate reserve (HRR).

HRR = MHR − RHR

MHR:190 bpm

Resting HR:65 bpm

Intermediate: 190 − 65

Result: HRR = 125 bpm

Step 4

Apply Karvonen at the lower intensity for the zone floor.

Target = RHR + HRR × intensity%

RHR:65 bpm

HRR:125 bpm

Intensity:60%

Intermediate: 65 + 125 × 0.60

Result: Zone low = 140 bpm

Step 5

Apply Karvonen at the upper intensity for the zone ceiling.

Target = RHR + HRR × intensity%

RHR:65 bpm

HRR:125 bpm

Intensity:70%

Intermediate: 65 + 125 × 0.70

Result: Zone high = 153 bpm

Step 6

Fill the standard 50–100% ladder plus fat-burn, cardio, peak, and the simple 50–85% MHR band.

Zone band = RHR + HRR × band%; Simple band = MHR × %

Fat-burn 60–70%:140–153 bpm

Cardio 70–80%:153–165 bpm

Peak 80–90%:165–178 bpm

Intermediate: Simple 50% = 95 bpm; 85% = 162 bpm

Result: Target 140–153 bpm; simple band 95–162 bpm

Final Answer

190 bpm

Worked Examples

See how the calculator works with different scenarios.

Scenario

A 30-year-old with resting HR 65 wants a fat-loss zone at 60–70% with the classic 220 − age estimate.

Inputs

Age:30 years

Resting HR:65 bpm

Method:Fox (220 − age)

Intensity:60–70%

Calculation

MHR = 220 − 30 = 190 bpm HRR = 190 − 65 = 125 bpm Low = 65 + 125 × 0.60 = 140 bpm High = 65 + 125 × 0.70 = 152.5 ≈ 153 bpm

Result

Target 140–153 bpm; simple 50–85% band 95–162 bpm

Interpretation

Hold 140–153 bpm for steady Zone 2 work you can talk through. The wider 95–162 bpm simple band confirms the Karvonen target sits in the moderate-to-vigorous window.

Understanding Your Result

Your Result: Max Heart Rate (MHR): 190 bpm bpm

Typical range: Resting 60–100 bpm (athletes 40–60); Zone 1 50–60%, Zone 2 60–70%, Zone 3 70–80%, Zone 4 80–90%, Zone 5 90–100%; general-health shortcut 50–85% of MHR.

What This Means

Each figure is a beats-per-minute band: MHR is your estimated ceiling, HRR is the usable range above rest, and the Karvonen targets map your chosen intensity onto that range. Fat-burn, cardio, and peak split the ladder into training purposes.

Why It Matters

Training at the wrong intensity wastes sessions — too easy builds little, too hard prevents consistency. Zones keep easy days easy and hard days hard, which is how aerobic fitness actually improves.

Professional Interpretation

Coaches anchor volume in Zone 2, add Zone 3 tempo for threshold, and reserve Zones 4–5 for short intervals. A falling resting HR at the same pace and faster 1-minute recovery signal adaptation.

Recommendations

•Put 80% of weekly minutes in Zones 1–2
•Cap recovery days to Zone 1 by the talk test
•Use Zone 3 tempo for 20–40 min sustained efforts
•Limit Zones 4–5 to 1–2 interval sessions weekly
•Re-measure morning resting HR monthly
•Confirm vigorous zones with a clinician if at risk

Educational Content

Introduction

The Target Heart Rate Calculator converts age and resting HR into a personalized training ladder. It estimates MHR two ways, derives HRR, and applies the Karvonen formula across the five classic zones plus the quick 50–85% MHR band.

Concept Explanation

Max minus rest is the range you can train in. Intensity picks the fraction of that range: 60% is easy aerobic, 80% is threshold, 90%+ is maximal. Tanaka softens the age decline for older adults versus the steeper Fox line.

Applications

▸Setting Zone 2 fat-burn sessions for weight management

▸Pacing tempo runs and rides in Zone 3

▸Programming HIIT intervals in Zones 4–5

▸Keeping recovery days truly easy in Zone 1

▸Comparing Fox vs Tanaka MHR estimates

▸Using the 50–85% band when resting HR is unknown

Benefits

•Personalizes targets with resting HR
•Prevents easy days from drifting too hard
•Makes interval prescriptions concrete
•Shows both formulas side by side
•Works with the talk test when no monitor is worn

Limitations

•Age formulas carry ±10–12 bpm population error
•Drugs, heat, altitude, and fatigue shift HR
•Wrist sensors lag on short intervals
•Max is estimated, not measured by graded test

Best Practices

•Measure resting HR on three calm mornings and average
•Wear a chest strap for intervals
•Confirm zones with the talk test and RPE
•Re-check targets after fitness or medication changes
•Progress Zone 4–5 time gradually

Common Misconceptions

Myth: 220 − age is exact for everyone.

Truth: It is a population line with ±10–12 bpm scatter. Tanaka is often closer in adults, and a lab test is the only individual max.

Myth: Fat-burn zone burns the most fat overall.

Truth: It burns the highest share from fat, but higher intensities burn more total calories. Total deficit plus Zone 2 volume wins.

Myth: Higher HR always means better workout.

Truth: Chronic Zone 4–5 without easy volume stalls progress and raises injury risk. Most gains come from Zone 2 consistency.

Myth: If HR will not enter the zone the monitor is broken.

Truth: Fatigue, heat adaptation, high fitness, or rate-control drugs can all blunt HR. Cross-check perceived exertion and context first.

Practical Tips

•Measure resting HR before caffeine, three mornings in a row
•Default to Tanaka after age 40 for a fairer max
•Nasal-breathing pace usually marks Zone 2 ceiling
•Cap warm-up and cool-down to Zone 1 (50–60%)
•Slow 10–15 bpm on hot or high-altitude days
•Re-run the calculator when resting HR drops 5+ bpm
•Clear Zones 4–5 with a clinician if previously inactive

Common Mistakes

Using %MHR when resting HR is known

Use Karvonen targets instead — %MHR can miss by 10–20 bpm for low- or high-resting adults.

Training every session in Zone 3

Polarize: keep easy days in Zone 1–2 and push only 1–2 interval days into Zones 4–5.

Chasing Zone 5 without a base

Build 4–6 weeks of Zone 2 volume first, then add short Zone 4 intervals with full recovery.

Trusting a single wrist spike

Smooth over 10–30 seconds and confirm with feel — optical sensors overshoot on sprints and lifting.

Forgetting heat and drift

Expect 5–15 bpm upward drift on long or hot sessions and pace by zone plus talk test, not pace alone.

Assumptions

This calculator makes the following assumptions to provide estimates:

Age 10–100: Ages outside 10–100 are clamped; estimates are least reliable in children and the very elderly.

Resting HR 30–120: Resting values are clamped to 30–120 bpm and assumed measured calm and caffeine-free.

Population MHR Lines: Fox and Tanaka are regression averages with roughly ±10–12 bpm individual error.

Steady-State Zones: Bands assume steady effort; intervals, hills, and drift move instantaneous HR.

No Rate-Altering Drugs: Targets assume no beta-blockers or stimulants unless a clinician adjusts them.

Limitations

Be aware of these limitations when using this calculator:

Population Estimate: Age-predicted max can err by ±10–12 bpm; a supervised graded test is the individual standard.

No Clinical Context: Calculator does not account for heart disease, hypertension, medications, or symptoms.

Sensor & Condition Noise: Heat, dehydration, altitude, caffeine, stress, and wrist-sensor lag shift readings.

Not a Prescription: Zones guide general fitness; vigorous training after inactivity needs medical clearance.

Frequently Asked Questions

Answers to common questions about this calculator.

What is target heart rate?

Target heart rate is the range of beats per minute you aim to hold during exercise for a chosen goal. It is usually expressed as a percentage of maximum heart rate (MHR) or of heart rate reserve (HRR) with the Karvonen formula.

How do I calculate my target heart rate?

Estimate MHR from age (220 − age or 208 − 0.7 × age), subtract resting HR to get HRR, then apply Target = RHR + HRR × intensity%. Without a resting HR, use the simple method MHR × intensity%.

What is the Karvonen formula?

Karvonen personalizes the target with resting HR: HRR = MHR − RHR, then Target HR = RHR + HRR × desired intensity. It is more accurate than MHR × % alone because it accounts for individual resting differences.

What is heart rate reserve (HRR)?

HRR is MHR minus resting HR (MHR − RHR). It is the beats available for exercise. A larger HRR generally reflects better cardiovascular fitness and widens every Karvonen zone.

What is maximum heart rate (MHR)?

MHR is the highest rate your heart can reach in maximal effort. Common estimates are Fox 220 − age and Tanaka 208 − 0.7 × age. Both are population averages with about ±10–12 bpm error.

What is resting heart rate (RHR)?

RHR is beats per minute at complete rest, best measured in the morning before rising. Normal adults are 60–100 bpm; trained athletes are often 40–60 bpm.

Which MHR formula should I use: 220 − age or Tanaka?

Fox (220 − age) is simple and widespread; Tanaka (208 − 0.7 × age) fits adults better, especially over 40, and avoids overestimating max in older adults. This calculator shows both so you can compare.

What are heart rate zones?

Five standard bands: Zone 1 50–60% very light, Zone 2 60–70% light, Zone 3 70–80% moderate, Zone 4 80–90% hard, Zone 5 90–100% maximal. Each stresses a different energy system.

What is Zone 2 training?

Zone 2 is 60–70% intensity at a conversational pace. It builds aerobic base, fat oxidation, and mitochondrial density. Many endurance plans put about 80% of volume here.

What is the fat-burning zone?

Usually 60–70% intensity where a higher share of calories comes from fat. Total calories are lower than at higher intensity, so overall deficit and total expenditure matter more for weight loss than the fuel mix.

What is the cardio zone?

Typically 70–80% intensity. It improves aerobic power and cardiac output and is the core zone for general cardiovascular fitness and tempo work.

What is the peak zone?

Usually 80–90%+ intensity. It builds lactate threshold, speed, and anaerobic power but can only be held for short intervals with recovery.

What is the simple 50–85% of MHR band?

The AHA-style band from 50% to 85% of MHR spans moderate to vigorous activity without using resting HR. It is a quick check when you only know age.

Karvonen vs %MHR: which is better?

Karvonen (with resting HR) is better for most adults because two people with the same age but resting rates of 55 and 80 get different targets. Use %MHR only when resting HR is unknown.

What is the target heart rate for weight loss?

Build volume in Zone 2 (60–70%) for long sustainable sessions, then add 1–2 higher-intensity sessions in Zones 3–4 for total calorie burn. Combine both rather than staying only in the fat-burn zone.

What is the target heart rate for beginners?

Start in Zone 1–2 (50–70%) with walk-jog or cycling intervals you can hold while talking in short sentences. Add Zone 3 time only after 3–4 consistent weeks.

What is the target heart rate for older adults?

Use Tanaka MHR, favor Zones 1–3 (50–80%), and clear vigorous exercise with a clinician first. Older adults often have higher resting rates and lower max, so Karvonen keeps targets realistic.

Can medications affect my heart rate zones?

Yes. Beta-blockers and some calcium-channel blockers blunt max and exercise HR; decongestants, stimulants, thyroid drugs, and asthma drugs can raise it. Ask your prescriber how to adjust zones.

Why is my exercise heart rate higher than predicted?

Heat, humidity, altitude, dehydration, caffeine, stress, poor sleep, illness, and cardiac drift on long sessions can add 5–20 bpm. Cool, hydrate, and compare like-for-like conditions.

What if my heart rate will not rise into zone?

Fatigue, overtraining, very high fitness, or rate-controlling drugs can blunt the rise. If maximal effort still will not reach Zone 3–4 repeatedly, seek medical review rather than forcing intensity.

What is the talk test?

If you can talk but not sing you are near Zone 2; short phrases only is Zone 3–4; single words or no speech is near maximal. It tracks Karvonen zones well when no monitor is available.

How accurate are wrist heart rate monitors?

Wrist optical sensors are usually within 3–5% on steady efforts but lag and err on intervals, lifting, and cold or tattooed wrists. Chest-strap ECG remains the accuracy standard.

How do I measure resting heart rate correctly?

Measure seated or lying after 5 calm minutes, ideally just after waking before caffeine or screens. Count a full 60 seconds or use a validated wearable average over several mornings.

How does fitness change resting and max heart rate?

Training lowers resting HR by raising stroke volume but barely changes age-predicted max. A falling resting rate at the same pace and faster recovery are signs of improving fitness.

When should I stop and seek care?

Stop for chest pain or pressure, faintness, unusually irregular rhythm, or HR far above target with symptoms. Seek prompt care for resting HR persistently above 100 with symptoms or syncope on exertion.

Do I need medical clearance before zone training?

Get clearance if you have heart disease, chest symptoms, uncontrolled hypertension or diabetes, or have been inactive and plan vigorous Zones 4–5. Start low and progress gradually.

Related Calculators

Explore more calculators related to this topic.

Related Guides

Deepen your understanding with these educational resources.

Zone 2 Training Basics

Build an aerobic base with conversational-pace volume.

HIIT Without Burnout

Place Zones 4–5 intervals around easy recovery days.

Heart Rate Monitors Compared

Chest strap vs wrist accuracy for steady and interval work.

Starting Cardio After 40

Tanaka targets, talk test, and clearance checklist.

Glossary

Technical terms used in mortgage calculations explained in plain language.

Maximum heart rate (MHR): Highest achievable beats per minute; estimated here by Fox 220 − age or Tanaka 208 − 0.7 × age.
Resting heart rate (RHR): Beats per minute at full rest; the Karvonen floor measured on calm mornings.
Heart rate reserve (HRR): MHR minus RHR; the beats available for exercise intensity.
Karvonen formula: Target = RHR + HRR × intensity%; personalizes zones with resting HR.
Zone 1 (50–60%): Very light recovery pace for warm-up, cool-down, and easy days.
Zone 2 (60–70%): Light fat-burn pace; conversational, sustainable for long sessions.
Zone 3 (70–80%): Moderate cardio pace improving aerobic power and threshold.
Zone 4 (80–90%): Hard peak pace for short intervals and speed work.
Zone 5 (90–100%): Maximal effort sustainable only for brief bursts.
Talk test: Field intensity check: full conversation ≈ Zone 1–2, phrases ≈ Zone 3–4, single words ≈ maximal.

Authoritative References

Trusted sources and standards referenced by this calculator.

American Heart Association — Target Heart Rates CDC — Target Heart Rate and Estimated Maximum Heart Rate ACSM — Guidelines for Exercise Testing and Prescription Tanaka et al. — Age-Predicted Maximal Heart Rate (JACC, 2001) Nes et al. — Age-Predicted Maximal Heart Rate (2013) Polar — Heart Rate Training Guide Garmin — Heart Rate Training for Athletes WHOOP — Heart Rate Variability (HRV) Guide

Applicable Standards

AHA target heart rate guidance (50–85% of MHR)ACSM Guidelines for Exercise Testing and Prescription

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Page Information

Last Updated:

2026-08-07

Version:

2.0.0

References:

License:

Free to use for educational and professional purposes.