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Zone 2 — Tanaka max HR

Enter your age and get your Zone 2 training range in beats per minute — the low-intensity zone that raises VO2 max with the least fatigue.

Free interactive tool

Zone 2 Heart Rate Calculator

Enter your age to estimate your zone 2 heart-rate band in beats per minute.

Age-based formulas carry ±10–15 bpm of individual variation. For a precise zone, use a lactate test (1.5–2.0 mmol/L) or a lab VO2 max assessment.

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Zone 2 heart rate by age

These bands come from the Tanaka max-HR estimate at 60–70%. Use them as a starting range and confirm with the talk test — Zone 2 is the hardest effort at which you can still speak in full sentences.

Age 25 — Zone 2 114–133 bpm
Estimated max HR 191 bpm
Age 30 — Zone 2 112–131 bpm
Estimated max HR 187 bpm
Age 40 — Zone 2 108–126 bpm
Estimated max HR 180 bpm
Age 50 — Zone 2 104–121 bpm
Estimated max HR 173 bpm
Age 60 — Zone 2 100–116 bpm
Estimated max HR 166 bpm

Why Zone 2 is the base every other zone sits on

At Zone 2 intensity your body draws most of its fuel from fat and trains the slow-twitch machinery — mitochondria and capillaries — that determines how much aerobic work you can sustain. Because it is low-stress, you can accumulate hours of it each week without the recovery cost of intervals, which is exactly why endurance coaches build 70–80% of total training volume here. Raise the floor with Zone 2 and every harder effort above it improves too.

Frequently asked questions

How do you calculate your Zone 2 heart rate?
Estimate your maximum heart rate with the Tanaka formula — 208 − (0.7 × age) — then take 60–70% of that number. For a 40-year-old, max HR ≈ 180 bpm, so Zone 2 lands at roughly 108–126 bpm. The calculator above does this for any age.
What does Zone 2 feel like?
Zone 2 is the highest effort at which you can still hold a full conversation in complete sentences. If you're gasping between words you've drifted into Zone 3; if you can sing comfortably you're likely in Zone 1. The talk test is a reliable cross-check when you don't have a heart-rate monitor.
Why train in Zone 2 specifically?
Zone 2 is the intensity where your body relies most on fat as fuel and where mitochondrial density and capillary networks adapt most efficiently. It builds the aerobic base that raises VO2 max over time — with far less fatigue and injury risk than high-intensity work, so you can accumulate more weekly volume.
Is the age formula accurate for me?
The Tanaka estimate (208 − 0.7 × age) is more accurate across ages than the old 220 − age rule, but it is still a population average — individual max HR varies by ±10–12 bpm. For a precise personal zone, use a lactate test (1.5–2.0 mmol/L) or a lab VO2 max assessment, and treat the calculator as a starting band.
Does Merios store these numbers?
No. The calculator runs entirely in your browser. Your inputs never leave your device and are not sent to a server.

Reference: Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol 2001;37(1):153-156.

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Your Zone 2 pace at the same heart rate is the clearest sign your engine is growing.

Merios overlays your resting heart rate and VO2 max trend with your blood markers — so aerobic progress shows up next to the labs it actually moves.

Get the appRead the Zone 2 guide →