Which zone is best for fat loss?

No single zone is best for fat loss. The 'fat burn zone' (low intensity) burns a higher percentage of calories from fat, but total calorie burn is lower than at higher intensities. The ACSM position stand on weight loss recommends ≥250 minutes per week of moderate-intensity exercise for significant weight loss. Consistency and total calorie deficit matter more than which fuel source your body uses during the workout.

Can I train in Zone 4 (80-90%) every day?

No. Zone 4 and Zone 5 training stresses the anaerobic system and central nervous system. Limit high-intensity work to 1-2 sessions per week, separated by at least 48 hours. Overtraining increases injury risk and reduces immune function.

Should my zones change as I get fitter?

Yes. As your resting heart rate drops, your heart rate reserve expands, and your Karvonen-calculated zones shift lower in absolute bpm. Recalculate every 8-12 weeks. If you use the simple %MHR method, your max HR does not change with fitness, so your zone numbers stay the same, but your perceived effort at those numbers will feel easier.

How do I measure my resting heart rate accurately?

Take it first thing in the morning, before getting out of bed, after a full night's sleep, with no caffeine in your system. Measure for 60 seconds. Do this for five consecutive mornings and average the results. A single measurement can be off by 10 bpm due to daily variation.

What if I am on a beta-blocker?

Beta-blockers lower your heart rate response to exercise, making all HR-based targets invalid. Use the Borg Rating of Perceived Exertion scale instead. Moderate intensity = RPE 12-13 (you can talk but not sing). Vigorous intensity = RPE 14-16 (you can say a few words). The AHA and ACSM both advise this adjustment.

What is the '226-age' formula for women?

There is no peer-reviewed evidence for this formula. It does not appear in any published study. The only female-derived formula with published data is the Gulati formula: 206, (0.88 × age) (Gulati et al., Circulation 2010). Use the Tanaka formula (208-0.7 × age) for adults over 40 regardless of sex.

Why does my watch show a different 'fat burn zone' than this chart?

Watch manufacturers use proprietary, often unsupported, algorithms. Many set the 'fat burn zone' at 60-70% of max HR, which is the same as Zone 2 in our table. The difference is in the marketing label, not the physiology. Ignore the label and focus on whether the intensity matches your goal (endurance vs. performance).

Target Heart Rate Chart by Age (With Training Zones)

A target heart rate chart by age allows you to look up your range without doing math every time you exercise. Bookmark the chart or print it. Every number in the tables comes from one of two formulas you can verify in one minute.

Find your personalised heart rate zones

Karvonen formula (Heart Rate Reserve method) with 5-zone model: 50-60%, 60-70%, 70-80%, 80-90%, 90-100% of HRR added to resting HR

Target Heart Rate Chart by Age: Moderate and Vigorous Ranges

The American Heart Association publishes a Target Heart Rates Chart using 50-85% of maximum heart rate (estimated by 220-age). The CDC refines that into two bands: moderate intensity (64-76% of max) and vigorous intensity (77-93% of max). Both sources use the same max-HR formula, so the charts below are consistent with what you will find at heart.org and the CDC's Measuring Physical Activity Intensity page.

How the chart is built: Max HR = 220-age. Moderate range = max HR × 0.64 to max HR × 0.76. Vigorous range = max HR × 0.77 to max HR × 0.93. All values rounded to the nearest whole beat per minute.

Target Heart Rate by Age (Moderate and Vigorous, Based on 220-Age Formula)

Age	Est. Max HR (bpm)	Moderate (64–76%)	Vigorous (77–93%)
20	200	128–152	154–186
25	195	125–148	150–181
30	190	122–144	146–177
35	185	118–141	142–172
40	180	115–137	139–167
45	175	112–133	135–163
50	170	109–129	131–158
55	165	106–125	127–153
60	160	102–122	123–149
65	155	99–118	119–144
70	150	96–114	116–140

Heart Rate Zones Chart by Age: Five Zones (Percent of Max)

Training zones separate your heart rate into five ranges, each with a different physiological effect. The percentages below use the simpler percent-of-maximum-heart-rate (%MHR) method. For a more personal calculation, see the Karvonen formula section further down.

These zones are standard across most training frameworks, though the exact labels vary. The numbers come from the ACSM's guidelines for exercise intensity, cross-checked against the AHA's 50-85% range.

Five Heart Rate Zones by Age (Percent of Max HR)

Age	Max HR	Zone 1 (50–60%)	Zone 2 (60–70%)	Zone 3 (70–80%)	Zone 4 (80–90%)	Zone 5 (90–100%)
20	200	100–120	120–140	140–160	160–180	180–200
30	190	95–114	114–133	133–152	152–171	171–190
40	180	90–108	108–126	126–144	144–162	162–180
50	170	85–102	102–119	119–136	136–153	153–170
60	160	80–96	96–112	112–128	128–144	144–160
70	150	75–90	90–105	105–120	120–135	135–150

What Each Zone Feels Like and What It Trains

Zone 1 (50-60% of max HR): Warm-Up and Recovery

You can talk normally. Breathing is easy. This zone trains blood flow to muscles and prepares the body for harder work. Use it for the first 5-10 minutes of any session and for active recovery days. It does not produce significant cardiovascular adaptation on its own.

Zone 2 (60-70% of max HR): Aerobic Endurance

You can hold a conversation but feel slightly breathless. This is the zone that improves mitochondrial efficiency and fat oxidation, often called Zone 2 heart rate in endurance training. It is not the same as the misleading "fat burn zone" (see below). Most of your weekly cardio volume should land here if your goal is aerobic base building.

Zone 3 (70-80% of max HR): Cardiovascular Fitness

You can say a few words at a time. This is moderate-to-vigorous aerobic exercise. It improves stroke volume, lung capacity, and heart efficiency. If you are training for general fitness, spend the majority of your workout time in this range.

Zone 4 (80-90% of max HR): Anaerobic Threshold

Speaking is limited to short phrases. This zone pushes your lactate threshold higher, meaning you can sustain high effort longer. Use interval training (30 seconds hard, 60 seconds easy) to reach this zone safely. Limit work here to 1-2 sessions per week.

Zone 5 (90-100% of max HR): Maximum Effort

All-out sprinting or a final push that lasts seconds. You cannot maintain it beyond a minute. This develops explosive power and speed. It is for advanced athletes only, after a thorough warm-up and conditioning base.

Personalising the Chart With the Karvonen Formula

The charts above assume a resting heart rate of zero, meaning they use percent of max HR, not heart rate reserve. The Karvonen formula (Karvonen, Kentala & Mustala, 1957) adds your resting heart rate into the calculation, making the target more individual. The formula is: Target HR = ((Max HR, Resting HR) × %Intensity) + Resting HR. The term "heart rate reserve" (HRR) is the difference between max and resting.

Example: A 40-year-old with a resting heart rate of 65 bpm. Max HR = 180 bpm (220-40). HRR = 115 bpm. To train at 70% intensity: (115 × 0.70) + 65 = 145.5 bpm. At the same 70% using the %MHR method: 180 × 0.70 = 126 bpm. The Karvonen method gives a higher target because it accounts for the resting baseline. For most people, the %HRR target at a given percentage is roughly 10-15 bpm higher than the %MHR target. The ACSM considers %HRR equivalent to %VO2R, making it the more physiologically sound method for prescription. Run a Karvonen formula target heart rate calculator once with your actual resting HR to get your personal zones.

Why Your Numbers May Differ From the Chart

Several factors can make your real target heart rate drift away from any printed chart. The most common reasons:

The 220-age formula has a standard deviation of ~12 bpm. Robergs & Landwehr (2002) showed this formula was never validated on a representative sample. Two people of the same age can have true max HRs 20+ bpm apart. For adults over 40, the Tanaka formula (208-0.7 × age) is more accurate. For women, the Gulati formula (206-0.88 × age) may be better (Gulati et al., Circulation 2010).
Resting heart rate varies day to day. A single morning measurement can be off by 10 bpm due to hydration, sleep quality, caffeine, or illness. The AHA lists a normal resting heart rate as 60-100 bpm. Always average several readings over a week.
Beta-blockers and other medications. Drugs like metoprolol suppress heart rate response. The AHA and ACSM both advise using perceived exertion (RPE) rather than heart rate targets if you take a beta-blocker. Use the Borg RPE scale: moderate intensity = 12-13, vigorous = 14-16.
Heart rate lags behind effort. During interval training, your HR may not catch up for 30-90 seconds. This makes HR-based zones less reliable for high-intensity work. Power-based zone models (Coggan, Friel) are more precise for cyclists and runners who use lactate threshold data.
Pregnancy. ACOG (2020) and the 2019 Canadian Guideline recommend using RPE (the "talk test") instead of a specific heart rate number. No target heart rate chart applies during pregnancy.

Printable Version: What to Take With You

Print the age table in five-year steps.

Write your personal resting heart rate on the same sheet. If you use the Karvonen formula, recalculate every three months, as your resting HR drops with fitness, your zones shift. Ignore any wrist monitor’s built-in “fat burn zone”; the ACSM position stand on weight loss (Donnelly et al., 2009) confirms that total calorie deficit, not fuel source during exercise, drives fat loss. The “fat burn zone” is a marketing term, not a training prescription.