Zone 2 Heart Rate Calculator
Find your exact Zone 2 training range — the fat-burning, aerobic base-building sweet spot — based on your age and resting heart rate.
💬 The Talk Test for Zone 2
In Zone 2, you should be able to hold a full conversation without gasping. If you can only say a few words, you're in Zone 3 or higher. If you could easily sing, you're probably in Zone 1. Adjust your pace until you can talk comfortably but not effortlessly.
What is Zone 2 training?
Zone 2 is the second of five heart rate training zones, sitting at 60–70% of your maximum heart rate (or 60–70% of your Heart Rate Reserve using the Karvonen method). It feels like a comfortable, sustainable effort — you can breathe through your nose and hold a conversation.
Despite feeling easy, Zone 2 is one of the most powerful training zones for long-term health and athletic performance. It targets the aerobic energy system directly, training your body to burn fat as its primary fuel source.
Why Zone 2 matters so much
Zone 2 training has gained enormous attention in endurance sports and longevity research. Here's why:
- Builds mitochondrial density: Zone 2 increases the number and efficiency of mitochondria in your muscle cells — the engines that produce energy aerobically.
- Improves fat oxidation: Your body becomes better at burning fat for fuel, which matters both for endurance performance and body composition.
- Enhances cardiovascular efficiency: Stroke volume (how much blood your heart pumps per beat) increases, meaning your heart gets stronger with less stress.
- Supports recovery: Low enough intensity to promote blood flow and recovery without adding training stress.
- Longevity benefits: VO2 max — heavily influenced by Zone 2 training — is one of the strongest predictors of long-term health outcomes.
How much Zone 2 should you do?
For recreational fitness, aim for 150–180 minutes of Zone 2 per week. Elite endurance athletes often do 80% of their total training volume in Zone 2 — the so-called "80/20 rule." Even 3 sessions of 45–60 minutes per week will produce meaningful aerobic adaptations over time.
Best activities for Zone 2
Any aerobic activity works — the key is keeping your heart rate in range. Running, cycling, rowing, swimming, and brisk walking are all effective. Cycling and rowing are especially useful because they're lower impact and easier to stay in Zone 2 without accidentally spiking into Zone 3.
Karvonen vs. % of Max HR
The Karvonen method accounts for your resting heart rate, making zones more personalised. It's particularly useful for people with a low or high resting HR. The % of Max HR method is simpler and works well for most people as a starting point.