Health & Fitness

Target Heart Rate Zones

Calculate all five heart rate training zones from your age and resting HR.

Heart rate zones define different intensity levels of cardiovascular training. Each zone produces different physiological adaptations — from fat burning to VO2 max improvement. Training in the right zone for your goals makes exercise measurably more effective.

Enter your numbers

Age

Resting Heart Rate (BPM)

Measure first thing in the morning before getting up.

Results update as you change the inputs. Calculations run in your browser.

Max Heart Rate

185 BPM

zone1 Warmup: 124-136 BPM (Warm-Up)
zone2 Fat Burn: 136-148 BPM (Fat Burn)
zone3 Aerobic: 148-160 BPM (Aerobic)
zone4 Threshold: 160-173 BPM (Lactate Threshold)
zone5 V O2 Max: 173-185 BPM (VO2 Max)

See the formula

Formula and method

HRmax = 220 - Age; Target Zone = RestingHR + (HRmax - RestingHR) × Zone%

Uses the Karvonen formula (Heart Rate Reserve method) which is more accurate than simple max HR percentage because it accounts for individual fitness level through resting heart rate.

Worked examples

Recreational runner, 35

Age:: 35
Resting Heart Rate (BPM):: 58

Max Heart Rate: 185 BPM

Sedentary beginner, 50

Age:: 50
Resting Heart Rate (BPM):: 75

Max Heart Rate: 170 BPM

Assumptions and limits

220 - age max HR formula (approximate)
Karvonen HRR method for zone calculation

This tool provides an educational estimate. Rules, rates and personal circumstances can change the answer. Review the assumptions before relying on a result. Report a correction.

Common mistakes to avoid

Using percentage of max HR directly — the Karvonen formula (using HRR) is more accurate.
Using an inaccurate resting HR — measure on multiple mornings before getting up.
Ignoring zone 2 (fat burn) training — most recreational athletes overtrain in zone 3 and under-utilize zone 2.

Frequently asked questions

Why is zone 2 so important?

Zone 2 training (60-70% max HR) builds mitochondrial density and improves fat oxidation. It is the foundation of aerobic fitness and recovery. Elite endurance athletes spend 80%+ of training time in zone 2.

Is the 220 - age formula accurate?

It is an estimate with roughly ±10-15 BPM accuracy. For a more precise max HR, perform a supervised max effort test. Genetically, max HR varies significantly from the formula at any given age.