Heart Rate Zone Calculator
Find your five training heart rate zones based on your age, so you can train at the right intensity for your goals.
*Estimates only, based on population-average formulas. Not medical advice — consult a doctor before starting a new high-intensity exercise program.
Want to know your daily calorie burn too?
TDEE Calculator❤️ Training By Heart Rate
Structuring workouts around heart rate zones helps you train with purpose instead of guessing effort.
How it Works
First we estimate your maximum heart rate from your age, then split that number into five percentage-based zones, each associated with a different training intensity and physiological benefit.
The Formula
Max HR = 220 − Age (Fox) or 208 − (0.7 × Age) (Tanaka). Each zone = Max HR × zone percentage range.
Pro Tip
Spend most of your weekly training volume in Zone 2 — it builds aerobic endurance without excessive fatigue, letting you recover fast enough for quality high-intensity sessions.
Frequently Asked Questions
How do I calculate my max heart rate? +
The classic formula is 220 minus your age. A more research-backed alternative, the Tanaka formula, is 208 minus (0.7 × age), which tends to be more accurate for older adults. Both are population averages — a lab-based VO2 max test is the only way to get your exact number.
What are the five heart rate training zones? +
Zone 1 (50-60% of max HR) is very light recovery activity. Zone 2 (60-70%) is light aerobic, fat-burning pace. Zone 3 (70-80%) is moderate aerobic/tempo. Zone 4 (80-90%) is hard, threshold-level effort. Zone 5 (90-100%) is maximum effort, used for short, high-intensity intervals.
Which zone should I train in most? +
Most endurance coaches recommend spending roughly 70-80% of training time in Zones 1-2 (easy, conversational pace) to build an aerobic base, with the remaining 20-30% in Zones 4-5 for intensity. This "polarized training" approach is common among elite endurance athletes.
What is the difference between the 220-age and Tanaka formulas? +
The 220-age formula (Fox, 1970) is simple but tends to overestimate max HR in younger people and underestimate it in older adults. The Tanaka formula (208 - 0.7×age), published in 2001 from a larger dataset, is generally considered a more accurate average, especially for people over 40.
Why does my watch show a different max heart rate? +
Fitness trackers often estimate max HR from formulas too, or they learn from your highest recorded heart rate during workouts. If you've genuinely hit a higher heart rate during intense exercise, that measured value is usually more accurate than any formula-based estimate.
Is a higher heart rate always bad? +
No — reaching Zone 4 or 5 during intense exercise is normal and often the training goal for interval workouts. What matters is your resting heart rate trend and whether your heart rate recovers normally after exercise. If you have a heart condition or unusual symptoms, consult a doctor before high-intensity training.