What is target heart rate?
Training heart-rate zones slice your effort into five bands between resting and maximum: recovery, aerobic base, tempo, threshold and VO2 max. Training in the right band is what turns running from random suffering into a progression.
How the calculator works
We estimate your maximum heart rate with either the Tanaka formula (208 − 0.7 × age — more accurate for anyone over 40) or the classic 220 − age, then cut the span into the five standard zones. Enter your resting heart rate and the tool switches to the Karvonen method, which reserves a band for cardiac drift and is noticeably more accurate for trained athletes.
Common use cases
- Programming zone-2 base miles
- Capping easy days so recovery runs stay easy
- Targeting threshold work for 5K–10K racing
Formula & caveats
Karvonen: target = resting + (max − resting) × intensity. Real max HR varies ±10 bpm from any formula — if a zone feels wrong, trust effort and adjust the max by feel.
Frequently Asked Questions
Which max-HR formula is better?
Tanaka tracks measured maxima better across ages, especially over 40. The classic 220−age is fine as a rough guide.
What should my resting heart rate be?
Typical adults 60–80 bpm; endurance athletes often 40–55. A rising trend can signal fatigue or illness.
Where should easy runs sit?
Zone 2 — roughly 60–70% of max HR, or the pace where you can hold a conversation.
Privacy & Your Data
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