Cardio Zone Training Planner

Plan your cardio workouts by calculating your personal heart rate training zones. This tool uses your age and resting heart rate to estimate zones for fat burning, aerobic endurance, and high-intensity training. Supports both metric (bpm) and US customary units. Everything runs in your browser—no data is sent online.

Educational only, not medical advice. Consult a professional before starting a new exercise program.

Calculate Your Zones

Heart Rate Units

Your Age (years)

Typical range: 18–80 years.

Resting Heart Rate (bpm)

Measure after waking, before getting up. Average is 60–100 bpm.

Maximum Heart Rate Formula

Decimal Places

Your Heart Rate Training Zones

Estimated Maximum HR: 185 bpm

Heart Rate Reserve (HRR): 120 bpm

Zone 1 – Very Light 50–60%

Recovery, warm-up, active rest.

125–137 bpm

Zone 2 – Light 60–70%

Fat burning, aerobic base building.

137–149 bpm

Understanding Heart Rate Training Zones

Training zones help you structure cardio workouts for specific goals, like improving endurance or boosting speed. Using your personal heart rate zones ensures you train at the right intensity.

How to Use This Tool

Enter your age and resting heart rate (measure after waking, before getting out of bed).
Select a formula for estimating maximum heart rate. The Haskell & Fox formula (208 – 0.7 × age) is often more accurate for adults over 30.
Click “Calculate Zones” to see your five training zones based on the Karvonen (Heart Rate Reserve) method.
Use the slider to explore how a lower resting HR (a sign of improved fitness) expands your training range.

Example Calculations

Age	Resting HR	Max HR (Fox)	Zone 2 Range (60–70%)	Primary Use
30 years	60 bpm	190 bpm	138–151 bpm	Aerobic endurance
50 years	70 bpm	170 bpm	130–140 bpm	Fat burning

Typical Zone Ranges & Intensity

Zone	% of Max HR	% of HR Reserve	Perceived Effort	Goal
1 – Very Light	50–60%	40–50%	Easy, conversational	Recovery, warm‑up
2 – Light	60–70%	50–60%	Comfortable, steady	Aerobic base, fat burning
3 – Moderate	70–80%	60–70%	Challenging, deeper breaths	Aerobic endurance
4 – Hard	80–90%	70–80%	Hard, unable to talk much	Anaerobic threshold
5 – Maximum	90–100%	80–100%	All‑out, unsustainable	Speed, power

Frequently Asked Questions

How accurate are these estimated zones?

Estimates are based on population averages. Individual variation can be ±10–15 bpm. For precise zones, consider a supervised exercise test with gas analysis (VO₂ max test).

Which max‑HR formula should I use?

The Fox formula (220 – age) is simple but can over/underestimate. Haskell & Fox (208 – 0.7 × age) tends to be better for adults over 30. If you’re very fit, Gellish (207 – 0.7 × age) may be more appropriate.

How do I measure my resting heart rate properly?

Measure first thing in the morning, before sitting up. Use a heart rate monitor or count your pulse at your wrist or neck for 30 seconds, then multiply by 2. Do this for 3–5 days and average the readings.

When should I talk to a doctor about my heart rate?

If your resting heart rate is consistently above 100 bpm (tachycardia) or below 40 bpm (without being a highly trained athlete), or if you experience dizziness, chest pain, or shortness of breath during light exercise, consult a healthcare professional promptly.

Formulas & Assumptions

Maximum Heart Rate (MHR) formulas:
Fox: MHR = 220 – age
Haskell & Fox: MHR = 208 – (0.7 × age)
Gellish: MHR = 207 – (0.7 × age)

Heart Rate Reserve (HRR): HRR = MHR – Resting HR

Karvonen Method (training zones):
Zone HR = Resting HR + (% of HRR × HRR)

Zone boundaries: Z1: 40–50% HRR, Z2: 50–60%, Z3: 60–70%, Z4: 70–80%, Z5: 80–100%.

Rounding: All results rounded to the specified decimal places (default 1).

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Cardio Zone Training Planner

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