Zone 2 Heart Rate Calculator: Find Your Range by Age
Calculate your five heart rate training zones from age using the Tanaka formula, with optional Karvonen (heart rate reserve) targets from your resting pulse.
Processed entirely in your browser — nothing you enter here is ever uploaded.
Result
About this tool
This page opens the heart rate zone calculator with zone 2 highlighted — it computes all five zones from your age instantly, and the green band is the one everyone is asking about.
Zone 2 (roughly 60–70% of max heart rate) earned its reputation because it builds the aerobic engine: at this easy, conversational intensity you train fat metabolism and mitochondrial capacity while accumulating volume that harder running would not let you recover from. Endurance coaches assign most weekly hours here for a reason.
The practical test: you should be able to speak in full sentences. If your watch says zone 2 but you cannot talk, add your resting heart rate in the calculator — the Karvonen ranges it unlocks are usually more faithful for trained people than plain %HRmax.
Example. Age 40 produces a Tanaka maximum of 180 bpm and a classic maximum of 180 bpm, with zone 1 at 90 to 108 bpm.
Limit. Age must be from 10 to 100, and a resting heart rate, if entered, must be from 30 to 120.