❤️ Target Heart Rate Zones Calculator — Train at the right intensity for your goal.
bpm
Measure your resting heart rate first thing in the morning, before getting out of bed.
Estimated Max HR: 190 bpm | Heart Rate Reserve: 125 bpm
| Zone | % of Max HR | Heart Rate (bpm) | What It Feels Like | Best For |
|---|---|---|---|---|
| Zone 1 | 50–60% | 128–140 | Very light. Easy conversation. | Warm‑up, recovery, general health |
| Zone 2 | 60–70% | 140–153 | Light. Can talk, don’t really want to. | Fat burning, aerobic base, longevity |
| Zone 3 | 70–80% | 153–165 | Moderate. Short sentences only. | Cardio endurance, tempo training |
| Zone 4 | 80–90% | 165–178 | Hard. A few words at a time. | Lactate threshold, performance |
| Zone 5 | 90–100% | 178–190 | Maximum. Can’t speak. | Sprint intervals, VO₂ max boost |
Uses the Karvonen formula with estimated max HR (220 − age).
Author: Dr. Shirley Cheung | © theshirlshirl.com
Author: Dr. Shirley Cheung | © theshirlshirl.com
Why Train by Heart Rate Zone?
Not all exercise is created equal. Zone 2 builds your aerobic base and burns fat — that’s the “conversational” pace you’ve heard about in longevity research. Zone 4 and 5 push your limits and boost VO₂ max. This calculator uses the Karvonen formula — which factors in your resting heart rate for more personalised zones than the basic “220 minus age” method alone.
For a deeper dive, read our guide on Zone Two Training and why it’s the foundation of metabolic health.