Zone2CalUse a range, not a single bpm.
Most runners should treat Zone 2 as a controlled aerobic band, then cross-check with breathing, perceived effort, and long-run drift.
Heart Rate Toolkit
Dial in Zone 2, MAF, and LT heart-rate zones with one workflow.
Compare 220-age, Tanaka, and custom max HR values, overlay Karvonen (HRR) results, and connect the output to 80/20 mileage planning. Consistent aerobic control keeps easy days easy—and makes the hard days count.
What is a useful Zone 2 heart-rate target?
Karvonen is more personal when RHR is reliable.
Resting heart rate helps tailor zones to your current fitness, while percent-max HR is simpler when RHR data is inconsistent.
Recovery still overrides the calculator.
If fatigue, injury, illness, or low-energy signs persist, keep easy runs easy and reduce load before chasing higher zones.
💓 Zone 2 heart-rate calculator
Enter age and resting HR to calculate Zone 1–5, MAF 180, and weekly 80/20 mileage recommendations.
🎯 MAF 180 formula
Choose the modifier that best fits your health history and training consistency.
Maximum aerobic HR (MAF)
— bpm
Aim for MAF HR − 10 to MAF HR during easy aerobic runs.
📊 Full HR zone table
Zone 2 (aerobic base)
— bpm
—
Calculated max HR
— bpm
| Zone | % of max/HRR | bpm range | Primary purpose |
|---|---|---|---|
| Enter your age to view the table | |||
Frequently Asked Questions
These answers match the structured FAQ data on this page.
Is Zone 2 based on max HR or resting HR?
Both methods are used. Percent max HR uses only max HR, while Karvonen uses max HR and resting HR for more personalized zones.
What heart-rate range is Zone 2?
A common range is 60-70% of max HR, but this varies by athlete. Use your test data and perceived effort to refine it.
Should I use MAF or Karvonen?
MAF is useful for conservative aerobic control, while Karvonen offers finer control when resting heart-rate data is reliable.
Last updated: February 25, 2026