Your five zones in bpm, worked out by percentage of max or by Karvonen. Resting heart rate changes the easy zones most: with a slow resting pulse they move up 15 to 25 beats.
Leave empty to estimate it from your age.
Used only if max heart rate is empty (Tanaka formula).
Needed for Karvonen. Take it in bed, right after you wake up.
Enter your max heart rate or your age to see your zones.
Enter your max heart rate or your age to see your zones.
Both methods use the same five bands: 50–60, 60–70, 70–80, 80–90 and 90–100%. Don’t know your max? Leave it empty and the tool estimates it from your age with Tanaka (208 − 0.7 × age).
max HR × %
The default on most watches. With a max of 190, zone 2 (60–70%) is 114–133 bpm. Your resting heart rate doesn’t come into it, so if yours is low, your easy zones come out too low.
Not sure of your max? Compare formulas in the max heart rate calculator.
resting HR + % × (max HR − resting HR)
The percentage applies to your heart rate reserve, the gap between your resting and max heart rates. With 190 and 60, the reserve is 130 bpm and zone 2 runs from 60 + 0.6 × 130 = 138 to 60 + 0.7 × 130 = 151 bpm.
Here, zone 2 is 60–70% of your max heart rate, or 60–70% of your heart rate reserve with Karvonen. With a max of 190 and a resting rate of 60, that’s 114–133 bpm by % of max, or 138–151 bpm by Karvonen. The conversational easy run most coaches call zone 2 usually lands in the Karvonen range.
If you know your resting heart rate, use Karvonen: it fits the zones to your actual working range. A low resting rate gives you higher easy zones that match how the run feels. % of max needs one number, and it’s what most watches use out of the box.
Zone edges are a convention. Garmin and Polar default to the same five bands as this tool (50, 60, 70, 80 and 90% of max); other systems start from lactate threshold. Check that your watch uses the same max, the same method (% of max or % of reserve) and the same percentages, then copy the numbers into Garmin Connect or Polar Flow.
Lying in bed right after you wake up, before coffee, three or four mornings in a row, then average them. A chest strap or your watch’s overnight reading works. Illness or a hard workout the day before pushes it up. A short night matters less than you’d think: across six controlled trials, sleep restriction added 2 bpm on average, too small to tell from noise.
In zones 1 and 2, fat covers a bigger share of the energy, but you burn more calories overall running faster. For runners, zone 2 is about building endurance with runs you can repeat day after day.