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Heart Rate Zone Calculator — Target HR & Training Zones

Enter your age to get your maximum heart rate and all five training zones in exact bpm — recovery, fat-burn, aerobic, threshold and VO₂ max. Add your resting heart rate for the more personal Karvonen targets. Works with any fitness watch. No signup, sources cited below.

By Induwara AshinsanaUpdated Jun 9, 2026
Your heart rate zones
ACSM zones · Tanaka 2001

Used to estimate your maximum heart rate (10–100).

Beats per minute at rest. Unlocks the more personal Karvonen targets.

Picks a recommended formula. You can override it on the right.

208 − 0.7 × age — Best general-population estimate (Tanaka et al., 2001).

Quick age
Maximum heart rate
187 bpm
Tanaka formula
Heart-rate reserve
122 bpm
HRmax − resting (Karvonen)
Fat-burn zone
112–131
Zone 2 · 60–70% HRmax (bpm)
AHA target band
94–159
50–85% HRmax (bpm)

HRmax by formula

Tanaka (recommended)
187bpm
208 − 0.7 × age
Fox (220 − age)
190bpm
220 − age
Gulati (women)
180bpm
206 − 0.88 × age

Five training zones

ZoneIntensity%HRmax (bpm)Karvonen (bpm)
Recovery
Zone 1		50%–60%94–112126–138
Fat burn
Zone 2		60%–70%112–131138–150
Aerobic
Zone 3		70%–80%131–150150–163
Threshold
Zone 4		80%–90%150–168163–175
Max effort
Zone 5		90%–100%168–187175–187
  • Fat burn: Builds your aerobic base and uses the highest share of fat for fuel. Easy, conversational pace.
  • Aerobic: Improves cardio-respiratory fitness and stamina. Moderately hard; talking gets harder.

A resting heart rate of 65 bpm sits inside the normal adult range of 60–100 bpm (American Heart Association).

Educational estimate only. Formula-based zones are not a substitute for medical advice. If you have a heart condition or are new to exercise, talk to a doctor before training near your maximum heart rate.

How it works

The calculator runs in three steps, all from published exercise-physiology formulas. Every value is rounded to the nearest whole beat per minute.

  1. Maximum heart rate (HRmax). By default it uses the Tanaka equation HRmax = 208 − 0.7 × age, the most accurate general-population estimate from a meta-analysis of 351 studies. You can switch to the familiar Fox rule (220 − age) or the women-specific Gulati equation (206 − 0.88 × age); the tool shows all three side by side so you can see how 220 − age tends to over-estimate.
  2. %HRmax zones. Each training zone is a band of intensity applied to your HRmax, following the American College of Sports Medicine classification: Zone 1 recovery 50–60%, Zone 2 fat-burn 60–70%, Zone 3 aerobic 70–80%, Zone 4 threshold 80–90%, and Zone 5 VO₂ max 90–100%. Each bound in bpm is simply the percentage multiplied by your HRmax.
  3. Karvonen (heart-rate-reserve) zones. When you enter a resting heart rate, the tool also computes heart-rate reserve HRR = HRmax − resting and then target = HRR × intensity% + resting. Because Karvonen adds your resting floor back in, its targets land a few beats higher than the matching %HRmax figure and are tailored to your own fitness. The calculator shows both columns so the difference is explicit.

As a plain-language cross-check, the American Heart Association recommends a moderate-to-vigorous training band of 50–85% of HRmax — shown in the results as the "AHA target band." All arithmetic is deterministic: there is no estimation beyond the cited formulas, and nothing is sent to a server. Your age and resting heart rate never leave your browser.

Worked examples

Age 30, resting 65 bpm, Tanaka

  1. HRmax = 208 − 0.7 × 30 = 187 bpm (Fox cross-check: 220 − 30 = 190)
  2. HRR = 187 − 65 = 122
  3. Zone 2 fat-burn (60–70% HRmax): 0.60×187 = 112 → 0.70×187 = 131 → 112–131 bpm
  4. Zone 2 Karvonen (60–70% HRR): 0.60×122+65 = 138 → 0.70×122+65 = 150 → 138–150 bpm
  5. Zone 4 threshold (80–90% HRmax): 0.80×187 = 150 → 0.90×187 = 168 → 150–168 bpm

Age 45, resting 72 bpm, female, Gulati

  1. HRmax = 206 − 0.88 × 45 = 166.4 → 166 bpm (Tanaka cross-check: 208 − 0.7×45 = 176.5 → 177)
  2. HRR = 166 − 72 = 94
  3. Zone 3 aerobic (70–80% HRmax): 0.70×166 = 116 → 0.80×166 = 133 → 116–133 bpm
  4. Zone 3 Karvonen (70–80% HRR): 0.70×94+72 = 138 → 0.80×94+72 = 147 → 138–147 bpm

Age 60, resting 60 bpm, Tanaka (edge of range)

  1. HRmax = 208 − 0.7 × 60 = 166 bpm
  2. HRR = 166 − 60 = 106
  3. Zone 1 recovery (50–60% HRmax): 0.50×166 = 83 → 0.60×166 = 100 → 83–100 bpm
  4. Zone 1 Karvonen (50–60% HRR): 0.50×106+60 = 113 → 0.60×106+60 = 124 → 113–124 bpm
  5. Note how Karvonen shifts the easy zone up once the resting floor is added.

Frequently asked questions

Sources & references

Formulas and intensity bands on this page were last cross-checked against the cited sources on 2026-06-09. This is an educational estimate, not medical advice — consult a doctor before starting vigorous exercise if you have a heart condition.

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