Heart Rate Zones Explained (and How to Find Yours)
Published June 6, 2026
Your heart rate is the most honest signal your body gives you during exercise. Training by zone turns that signal into a concrete plan so you stop guessing and start hitting your actual goal.
- Every zone is a percentage of your maximum heart rate (HRmax). Estimate it with 208 minus (0.7 times your age).
- Five zones cover very light (50-60%) through maximum effort (90-100%), each with a distinct training benefit.
- The Karvonen method folds in your resting heart rate for a more personal bpm target than plain percentages give.
- Most of your training time should be in Zones 1-2. Hard efforts in Zones 4-5 need only a small slice of your week.
Estimate your maximum heart rate first
Every zone is a percentage of HRmax, the highest beats per minute your heart can reach at all-out effort. A supervised exercise stress test measures it precisely, but most people estimate it with a formula.
The classic rule is 220 minus your age. The American Heart Association uses it as the basis for its target heart rate tables. A 40-year-old gets an estimated HRmax of 180 bpm.
A more accurate alternative comes from a 2001 meta-analysis by Tanaka and colleagues (Age-predicted maximal heart rate revisited) that pooled data from nearly 19,000 subjects:
For a 65-year-old, 220-age gives 155 bpm while Tanaka gives about 163 bpm, a gap large enough to shift your zone targets. Either estimate can be off by 10-20 bpm for any individual, so treat it as a starting point you refine with experience.
The five training zones
Once you have an HRmax, the standard model splits effort into five zones. The exact percentages vary slightly between organizations, but this five-zone framework is the most widely used.
Zone 1 (50-60%): Gentle warm-up or recovery pace. You can hold a full conversation easily. Good for beginners and active recovery days.
Zone 2 (60-70%): The “all-day” aerobic pace. Breathing deepens but talking stays comfortable. Endurance athletes spend most of their training time here, building the aerobic base and fat-burning efficiency.
Zone 3 (70-80%): Steady, purposeful effort. Conversation gets choppy. This is classic tempo work that develops aerobic capacity.
Zone 4 (80-90%): Genuinely uncomfortable. A few words at a time. Zone 4 raises your lactate threshold, which directly improves speed and race performance.
Zone 5 (90-100%): All-out effort lasting seconds to a couple of minutes. Reserved for short interval bursts. Builds peak power and maximum oxygen uptake, but demands adequate recovery time.
A quick sanity-check without a monitor is the talk test. The CDC’s guide to measuring physical activity intensity notes that during moderate activity you can talk but not sing, while during vigorous activity you can only manage a few words before pausing for breath. That maps to Zone 3 (moderate) and Zones 4-5 (vigorous).
Two ways to set your target bpm
Multiply HRmax by the zone percentage. Simple, works with any printed chart.
Zone 2 for HRmax 180: 108-126 bpm
Folds in your resting heart rate for a more personal target. Better for athletes or anyone with an unusually high or low resting rate.
Zone 2 with RHR 60, HRmax 180: 132-144 bpm
The Karvonen formula is: Target = ((HRmax - HRrest) x intensity %) + HRrest. The “reserve” is the range your heart actually has to work with. For a 40-year-old with HRmax 180 and RHR 60, the reserve is 120 bpm. Zone 2 bottom (60%) becomes (120 x 0.60) + 60 = 132 bpm, meaningfully higher than the 108 bpm the plain percentage method gives.
How to measure your resting heart rate accurately
Resting heart rate (RHR) for a typical adult falls between 60-100 bpm. A lower RHR generally signals better cardiovascular fitness: well-trained endurance athletes often sit in the 40s.
Take your pulse first thing in the morning, before getting out of bed and before caffeine.
Use your wrist (radial artery) or the side of your neck (carotid artery).
Count beats for 30 seconds and multiply by two. A full 60 seconds is more accurate.
Repeat for several mornings and average the results. A single reading can be skewed by sleep quality or stress.
A resting heart rate that climbs persistently over weeks can signal overtraining, illness, or stress. A fitness watch or chest strap tracks RHR automatically and tends to be more reliable than manual counting.
How to put the zones to work
Both the NHS and the American Heart Association recommend adults hit those activity targets. Heart-rate zones make sure your “moderate” and “vigorous” labels are actually accurate.
A common and well-supported approach for distributing effort is to spend the bulk of aerobic time in Zones 1-2 and reserve hard efforts (Zones 4-5) for a small fraction of your week. Staying stuck in Zone 3 all the time leaves you tired without the benefits of either truly easy or truly hard work.
Higher zones burn more calories per minute, but lower zones let you train far longer, so total burn is not as lopsided as it seems. If your goal is weight-related, pair zone training with the Calorie Calculator to handle the intake side.
Your zone-training checklist
This guide is for general education and isn’t medical advice. Heart-rate formulas are population estimates and may not fit you precisely. Talk to a doctor before starting a vigorous exercise program, especially if you have a heart condition, take medication that affects heart rate, or have been inactive.