Tool · Zone 2
Zone 2 heart rate calculator.
A zone 2 heart rate calculator only does arithmetic. Zone 2 means easy aerobic work, the kind where you can still talk. Three common methods give three different ranges. This page shows all three and writes the formula next to the number.
Not medical advice. If you have a heart condition, chest pain, or you take medicine that changes heart rate, including beta blockers, ask a doctor before you train by heart rate.
Three ways to estimate zone 2
Percent of max heart rate
Zone 2 is often written as 60 to 70 percent of max heart rate. When you do not enter a max, this calculator estimates max as 220 minus age. That is a population guess. It can miss a real max by a wide margin.
Karvonen, or heart-rate reserve
Heart-rate reserve is max minus resting heart rate. The zone 2 range here is resting heart rate plus 60 to 70 percent of that reserve. It needs a resting heart rate. Leave resting blank and this range stays empty.
MAF, 180 minus age
The basic MAF number is 180 minus age. Phil Maffetone’s method sometimes subtracts more beats for recent illness, injury, or some medicines, and adds beats in a few training cases. This calculator shows only 180 minus age.
The three methods disagree because they start from different inputs. Use them as a bracket, then use the talk test. If you cannot speak in full sentences, you are above zone 2, whatever the number says.
Calculate a range
Your three ranges will show here. Age is required. Resting and max are optional.
The talk test
During zone 2 you should be able to talk in full sentences. Short phrases mean the effort is higher than zone 2. A watch zone that disagrees with that is the one to distrust.
Related reading
- Running pace calculator
- Zone 2 training and slow running
- Is zone 2 overrated?
- Electrolyte drinks for runners
Common questions
What heart rate is zone 2?
Zone 2 is easy aerobic work. A common heart-rate version is 60 to 70 percent of max heart rate. Karvonen uses 60 to 70 percent of heart-rate reserve instead. MAF uses 180 minus age. The three numbers often do not match.
Why do the three zone 2 methods disagree?
They divide different numbers. Percent of max ignores resting heart rate. Karvonen includes it. MAF does not use a measured max at all. None of them knows how you feel. The talk test is the check: full sentences mean easy.
Is 220 minus age my max heart rate?
No. 220 minus age is a population estimate. A tested max can sit well above or below it. If you have a recent max from a hard effort or a lab, enter that. The percent method and Karvonen will use it.
What if I take a beta blocker?
Beta blockers and some other medicines slow heart rate. A formula can then call an effort easy when it is not. If you have a heart condition or take heart-rate medicine, ask a doctor before you train by heart rate.
What is the talk test?
You should be able to speak in full sentences during zone 2. A few words at a time means you are working harder than that, even if a watch still says zone 2.