Your Age

years

Resting Heart Rate (Recommended)

bpm

If you provide your resting heart rate, we use the highly accurate Karvonen formula (60-70% of HR Reserve). Otherwise, we use the standard 60-70% of Max HR formula.

Your Zone 2 Heart Rate

Beats Per Minute (BPM)

The Talk Test

While exercising in Zone 2, you should feel 'comfortable but purposeful'. You should be able to hold a full, continuous conversation without gasping for air. If you can't speak easily, you're going too hard.

Why Train in Zone 2?

Increases mitochondrial density and efficiency, building a massive aerobic base.
Improves your body's ability to burn fat as fuel, sparing glycogen.
Lowers resting heart rate and improves cardiovascular health without overtraining.
Aids in recovery from high-intensity workouts by clearing lactate.

Build Your Engine

Enter your age and resting heart rate to find your optimal Zone 2 training range.

Calculation Principles & Formulas

This tool uses the Tanaka formula to estimate Maximum Heart Rate. For calculating Zone 2 (60% - 70% intensity), it offers two methods depending on whether you provide a resting heart rate:

[Maximum Heart Rate Estimation] Max HR = 208 - (0.7 × Age) [Standard Formula (No Resting HR)] Zone 2 Lower Limit = Max HR × 60% Zone 2 Upper Limit = Max HR × 70% [Karvonen Formula (With Resting HR - Recommended)] Heart Rate Reserve (HRR) = Max HR - Resting HR Zone 2 Lower Limit = (HRR × 60%) + Resting HR Zone 2 Upper Limit = (HRR × 70%) + Resting HR

Note: Compared to simple age-based estimation, the Karvonen formula is highly recommended because it incorporates your resting heart rate. This reflects your current cardiovascular fitness, providing a much more accurate and personalized Zone 2 training range.