Heart Rate Zone Calculator
Find your five personal heart-rate training zones using your age (or measured max HR) and resting heart rate.
How to use the heart rate zone calculator
- Enter your age, or your measured maximum heart rate if you know it.
- Optionally add your resting heart rate for the more accurate Karvonen method.
- Click Calculate to see all five zones in beats per minute.
What each training zone is for
Zone 1–2 build aerobic base and aid recovery, Zone 3 is tempo/steady effort, Zone 4 raises lactate threshold, and Zone 5 develops top-end VO2 max. Most endurance plans spend the majority of time in Zones 1–2.
Why the Karvonen method is more personal
Simple zone calculators take percentages of your maximum heart rate alone. The Karvonen method adds your resting heart rate to work from your heart-rate reserve, the gap between rest and max, which reflects your individual fitness far better.
Two runners with the same max but different resting rates will get different, more appropriate zones from Karvonen. A fitter runner with a low resting rate gets zones that correctly demand a higher absolute heart rate for the same effort level.
How to actually use your zones
Most endurance improvement comes from spending the majority of your time in zones 1-2, easy enough to hold a conversation. Zone 3 builds steady stamina, zone 4 lifts your lactate threshold, and short bouts in zone 5 sharpen top-end fitness. A common mistake is running easy days in zone 3, too hard to recover but too easy to drive big gains, the so-called grey zone.
The five heart-rate zones (% of max HR)
| Zone | % of max HR | How it feels | What it trains |
|---|---|---|---|
| 1 · Very easy | 50–60% | Very light, chatty | Recovery and warm-up |
| 2 · Easy | 60–70% | Conversational | Aerobic base and fat use |
| 3 · Moderate | 70–80% | Working, shorter sentences | Aerobic endurance |
| 4 · Hard | 80–90% | Hard, only a few words | Lactate threshold |
| 5 · Maximal | 90–100% | All out | VO2 max and speed |
These bands are percentages of maximum heart rate. The Karvonen (heart-rate reserve) method shifts them slightly and personalises them using your resting heart rate, but the training purpose of each zone stays the same.
Frequently asked questions
How are heart rate zones calculated?
Zones are percentages of your heart-rate reserve (max HR minus resting HR) added back to resting HR — the Karvonen method. Without resting HR, zones use a simpler percentage of max HR.
What is the formula for maximum heart rate?
A common estimate is 220 minus your age. This tool uses the more accurate Tanaka formula (208 − 0.7 × age) when you don't provide a measured max.
Should I train by heart rate or by pace?
Both have a place. Heart rate is excellent for keeping easy runs genuinely easy and for racing in heat, while pace is better for precise interval targets. Many runners use heart rate to cap easy days and pace for hard sessions.
Why does my heart rate drift up on long runs at the same pace?
This is cardiac drift, caused mainly by rising core temperature and mild dehydration. It is normal, especially in heat, and is one reason heart-rate-capped easy running naturally slows you down late in a long run.
How do I find my resting heart rate?
Measure it first thing in the morning before getting out of bed, ideally averaged over several days. A wearable that tracks overnight heart rate gives a reliable figure.
What are the five heart-rate training zones?
They range from very easy recovery (50–60% of max) up to maximal efforts (90–100%), each training a different system, as shown in the table below. Spending most of your time in zones 1–2 builds the aerobic base that underpins everything else.
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FTP Calculator
Estimate your Functional Threshold Power from a 20-minute test and get your full set of power training zones.