Calculator
Heart rate zone calculator
Work out your maximum heart rate and your 5 training zones. Add your resting heart rate for more accurate, Karvonen-based zones.
Your details
Measured lying down after waking. With it, the zones use the more accurate Karvonen method.
Maximum heart rate
Training zones
Run most of your weekly training in zones 1–2; use the higher zones in targeted, rationed doses.
Zone 1 — Recovery
Active recovery, warm-up, cool-down. Primes the body for harder work.
· bpm
Zone 2 — Endurance
Builds the aerobic base, fat metabolism, capillary density. Most of your running lives here.
· bpm
Zone 3 — Tempo
Develops aerobic power and circulatory efficiency; marathon and tempo efforts.
· bpm
Zone 4 — Threshold
Raises lactate threshold and speed endurance; threshold and interval sessions.
· bpm
Zone 5 — VO2max / anaerobic
Maximum aerobic and anaerobic capacity, speed; short, hard repetitions.
· bpm
What are heart rate zones?
Heart rate zones are percentage bands of your maximum heart rate (or heart rate reserve) tied to different training effects. Training in the right zone develops the ability you want — and stops every session sliding into a "moderately hard" grey zone.
Maximum heart rate is estimated from a formula. 220 − age (Fox) is simple but inaccurate; Tanaka (208 − 0.7 × age) is more reliable for adults, and for women Gulati (206 − 0.88 × age) is recommended. A field test or a lab-measured individual max HR is more accurate than any formula.
The Karvonen method (heart rate reserve)
The Karvonen method uses heart rate reserve: HRR = max HR − resting HR, and the target = (HRR × intensity) + resting HR. Because it accounts for resting HR, which reflects fitness, the zones are more personalised and track actual effort better than plain %max HR.
Frequently asked questions
Which max HR formula should I choose?
In general, Tanaka is more reliable than the old 220 − age. For women, Gulati is recommended. If you know your true max HR from a field test or lab, that beats any formula.
Do I need my resting heart rate?
Not required. With it, the calculator uses the Karvonen method, which tailors the zones to your fitness. Without it, the zones come from a percentage of max HR.
How do I measure my resting heart rate?
In the morning, after waking, still lying down, measure calmly for a minute (or with a watch). An average of several mornings is most reliable.
Which zone should I run in most?
A large share of your weekly volume should be in zones 1–2 (easy, aerobic). Zones 4–5 are for 1–2 targeted sessions a week, with adequate recovery.
Heart rate numbers are formula-based estimates with individual variation (typically ±7–12 bpm). With any heart or circulatory condition, or before starting a new programme, consult your doctor.