DocomintHeart Rate Zone Calculator
Calculate target heart rate training zones from age — fat burn, cardio, and peak.
What is a Heart Rate Zone Calculator?
Training zones are defined as percentage bands of estimated maximum heart rate (220 minus age, a population-level formula) — from a light warm-up pace up to a maximum-effort zone — used by runners and cyclists to target a specific training effect (fat-burning endurance vs. cardiovascular peak effort) rather than just running at whatever pace feels arbitrary.
How to use the Heart Rate Zone Calculator
- Enter your age
- Press Calculate Zones
- Five heart rate training zones, in beats per minute, appear instantly, computed on your device
Formula
Max HR = 220 − Age | Zone range = Max HR × zone's percentage band
Each of the five zones is a percentage band of estimated maximum heart rate, from a light warm-up pace up to maximum effort.
Example
At age 35, estimated max heart rate is 185 bpm — the "fat burn" zone (60–70%) falls between 111–130 bpm, while the "cardio" zone (70–80%) runs 130–148 bpm, a noticeably different effort level for the same workout duration.
Common mistakes
- Treating 220−age as an exact personal number rather than a population average — individual max heart rate can genuinely vary by ±10-20 bpm from the formula's prediction.
- Training exclusively in one zone regardless of the actual workout goal — different zones suit different training purposes.
- Not accounting for medications like beta-blockers that can lower actual achievable heart rate below what the formula predicts.
Frequently asked questions
Is "220 minus age" an accurate max heart rate formula?
It's a widely used population-average estimate, but individual max heart rate can vary by ±10-20 beats from what the formula predicts — a lab-based fitness test gives a more personalized number if precision matters for your training.
Which heart rate zone should I train in?
It depends on your goal — lower zones (fat burn, light cardio) suit longer, lower-intensity endurance sessions, while higher zones (hard, maximum) suit shorter, high-intensity interval training. Most training plans mix multiple zones across a week rather than staying in just one.
Should I use a different formula if I'm very fit or unfit?
220−age is a broad population estimate regardless of fitness level — some alternative formulas (like the Tanaka formula) exist and can be slightly more accurate for certain groups, but a lab-based fitness test is the most personalized option if precision genuinely matters for your training.
What zone is best for fat loss?
The "Light (fat burn)" zone (60-70% of max HR) burns a higher proportion of calories from fat per minute, but higher-intensity zones burn more total calories per minute overall — total calories burned across a session matters more for fat loss than which zone produced them.
Is my numbers uploaded anywhere?
No — Heart Rate Zone Calculator runs entirely in your browser using JavaScript/WebAssembly. Your numbers is never sent to a server.