Calculate your 5 training heart rate zones using three different methods. Find the right intensity for every session, from easy recovery runs to maximum effort intervals.
Free to use
3 calculation methods
5 training zones
Weekly plan guide
Heart Rate Zones Calculator
5 training zones based on your max HR
% Max HR
Simple and widely used. Zones as % of max heart rate.
Karvonen
Uses heart rate reserve. More accurate, accounts for resting HR.
Lactate
Based on lactate threshold. Most accurate for trained athletes.
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Max Heart Rate
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Resting HR
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HR Reserve
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Method Used
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Heart Rate Spectrum
Recommended Weekly Distribution
Based on 80/20 polarised training
Max heart rate formulas are estimates. For the most accurate zones, consider a lab test or field test (e.g. 30-min all-out run for lactate threshold). Individual max HR can vary by -10-15 bpm from formula predictions.
The Guide
Heart Rate Training Zones Explained
Training in different heart rate zones develops different physiological adaptations. Each zone targets a specific energy system and produces specific benefits. Understanding and using zones correctly is what separates structured training from just going out and running hard every session.
The 5 Zones
Zone
% Max HR
Feel
Primary Benefit
Typical Use
Zone 1, Recovery
50-60%
Very easy, conversational
Active recovery, fat burning
Warm-up, cool-down, rest days
Zone 2, Aerobic
60-70%
Easy, can hold conversation
Aerobic base, fat metabolism
Long easy runs, base building
Zone 3, Tempo
70-80%
Moderate, breathing harder
Aerobic efficiency
Steady state, tempo runs
Zone 4, Threshold
80-90%
Hard, few words at a time
Lactate threshold, speed
Threshold intervals, race pace
Zone 5, VO2 Max
90-100%
Maximum effort
VO2max, speed, power
Short intervals, sprints
The 3 Calculation Methods
% Max HR is the simplest method, zones are calculated as fixed percentages of your maximum heart rate. It's widely used and sufficient for most recreational athletes.
Karvonen (Heart Rate Reserve) uses the difference between your maximum and resting heart rate (your "reserve"). It produces more personalised zones because it accounts for your fitness level, a fitter person with a lower resting HR will have different zones than a sedentary person at the same max HR.
Lactate Threshold anchors zones to your lactate threshold heart rate, the point at which lactate begins to accumulate faster than it can be cleared. This is the most physiologically meaningful anchor point for trained athletes, producing zones that align directly with metabolic states.
The 80/20 Rule
Research on elite endurance athletes consistently shows they spend approximately 80% of training time in Zones 1-2 (easy/aerobic) and only 20% at Zone 3 and above. This "polarised" approach builds a large aerobic base while allowing sufficient high-intensity work to improve speed. Most recreational runners make the mistake of doing most training at a "moderate" intensity, too hard to get the aerobic base benefits, too easy to drive speed improvements.
How to Find Your True Max HR
Age-based formulas are estimates with -10-15 bpm error. For more accurate zones, do a max HR test: after a thorough warm-up, run hard for 3 minutes, recover for 3 minutes, then run as hard as possible for 3-5 minutes to exhaustion. Your peak HR reading is close to your true MHR. Alternatively, a lab VO2max test will give you precise values for all zones.
Frequently Asked Questions
Several factors affect how a given heart rate feels: heat and humidity raise HR for a given effort; fatigue from previous days' training raises HR; dehydration raises HR; caffeine raises HR. Heart rate also drifts upward over the course of a long run at constant pace (called "cardiac drift"). This is why perceived effort and pace are useful alongside HR data, use all three together.
For beginners: % Max HR is sufficient and simple. For intermediate runners who know their resting HR: Karvonen gives more personalised zones. For trained athletes who have tested their lactate threshold (e.g. through a fitness test or a 30-minute all-out time trial): lactate-based zones are the most accurate. Start simple and progress to more precise methods as your training becomes more structured.
Yes, Zone 2 is arguably the most important zone for endurance athletes. It specifically develops mitochondrial density and fat oxidation capacity, which are the foundation of all endurance performance. Most recreational athletes severely underdevelop Zone 2 by running too hard on easy days. If you can't hold a comfortable conversation, you're probably not in Zone 2.
Yes, the zones apply to any cardio activity, but your absolute heart rates will differ between sports. Cycling HR is typically 5-10 bpm lower than running at the same effort because you're not supporting your bodyweight. Swimming HR is lower still. For best results, establish separate zones for each sport you train in, or use the running zones as a general baseline and expect slightly lower numbers on the bike.
Wrist-based optical HR monitors (Apple Watch, Garmin, Fitbit) are reasonably accurate at steady-state efforts, typically within 5 bpm. They are less accurate during high-intensity intervals, in cold weather, and when the device is loose on the wrist. For precise zone training, a chest strap (Garmin HRM, Polar H10) is significantly more accurate, particularly at high intensities. Arm-based monitors (Wahoo Tickr Fit) fall between the two in terms of accuracy.
