What Should Your Zone 2 Heart Rate Be by Age?

Your Zone 2 heart rate is about 60 to 70 percent of your max heart rate, and that band drops as you get older. For a 40-year-old, that is roughly 108 to 126 beats per minute. For a 25-year-old, closer to 116 to 136. But these numbers come from a formula. They are a starting point, not your exact zone. The real value hides behind a wide spread, and you tune it with a few simple field tests.

Age	Estimated max HR (bpm)	Zone 2: 60 to 70% of max (bpm)	Maffetone aerobic cap, 180 minus age (bpm)
20	194	116-136	150-160
30	187	112-131	140-150
40	180	108-126	130-140
50	173	104-121	120-130
60	166	100-116	110-120
70	159	95-111	100-110

What should your Zone 2 heart rate be by age?

Your Zone 2 heart rate is about 60 to 70 percent of your max heart rate. Your max heart rate falls as you age. So the Zone 2 band drifts a little lower each decade. The table above shows that drift across the ages.

Here is how the numbers are built. First, you estimate your max heart rate. A common formula is 208 minus 0.7 times your age. For a 40-year-old, that is about 180 beats per minute. Then you take 60 to 70 percent of that. For the same runner, that lands at 108 to 126 beats per minute. That band is the Zone 2 estimate.

This post is about those by-age numbers and how to trust them. It is not about what Zone 2 does to your body. If you want the full case for why easy aerobic running builds your engine, read our complete guide to Zone 2 running. For the full map of all five effort zones, see our breakdown of heart rate zones for running.

The age chart is useful. It gives you a number to start with on day one. But it carries a flaw you need to know about. The next section explains why.

Why is the by-age Zone 2 formula only a starting point?

The by-age formula is only a starting point because it hides a wide spread. Two runners the same age can have very different true zones. The chart prints one number. Real bodies do not agree with it.

The problem starts with max heart rate. The age estimate can miss your true max by 10 to 12 beats in either direction. We cover that gap in detail in our look at the 220 minus age myth. Since every zone is a percent of your max, a wrong max shifts your whole Zone 2 band with it.

The percent itself is not fixed either. The top of Zone 2 is your aerobic threshold, the point where lactate first starts to rise. That marker does not land at the same percent for everyone. A 2025 analysis of seven studies covering 140 runners found this threshold can fall anywhere from 69 to 94 percent of max heart rate (Davis, 2025). That is a huge range. It means a single percent rule cannot be right for every runner.

69 to 94%

of max heart rate where the Zone 2 ceiling can fall across runners (Davis, 2025)

A separate study put hard numbers on the cost. Researchers tested 165 recreational runners in a lab. They found that to keep every runner below that first threshold, the effort had to stay at or under 70 percent of max heart rate. No single fixed heart rate placed all of them in the same intensity zone (Nuuttila et al., 2025). The same age number meant easy work for one runner and too-hard work for another.

So the chart gets you close. Your own body sets the truth. That is why every smart runner treats the table as a first draft and then refines it.

What is the 180-minus-age (Maffetone) method?

The 180-minus-age method sets an aerobic heart rate ceiling instead of a percent of max. It is often called the MAF method or the Maffetone method. You subtract your age from 180. Then you adjust the result up or down based on your health and your training history. The final number is the top of a 10-beat aerobic band (Maffetone & Laursen, 2020).

A worked example helps. A healthy, consistent 40-year-old gets 140 from the rule. Their aerobic band runs from 130 to 140 beats per minute. A runner coming back from illness would subtract more and train lower. A long-time athlete with steady gains can add a few beats.

This method aims at fat-burning effort, not a slice of your max. So it can land higher or lower than the 60 to 70 percent band in the table. You can see that in the chart. The Maffetone cap often sits above the percent-of-max range.

Its main strength is a tight band. The percent-of-max approach can spread an aerobic target across more than 40 beats. The 180 method holds it to 10 beats (Maffetone & Laursen, 2020). A tighter target is easier to train inside.

But tighter is not the same as personal. The authors who reviewed the method are clear about its limit. Neither the 180 rule nor the 220 rule can replace a lab test for finding your real aerobic threshold (Maffetone & Laursen, 2020). It is a strong starting guess. It is still a guess.

How do you refine your personal Zone 2 with field tests?

You refine Zone 2 by testing your own body, not by trusting the chart. Three simple checks do most of the work. You need no lab and no extra gear.

The first is the talk test. Run easy, then try to speak. If you can hold full, calm sentences, you are in Zone 2. If words come in short bursts, you are over the line. This check reads your effort on the day, which a fixed number cannot. We explain how it maps to each zone in our heart rate zones guide.

The second is a field threshold check. Warm up, then run a hard, steady 30-minute solo effort. Take your average heart rate over the final 20 minutes. That number is close to your threshold, the hard ceiling well above Zone 2. Once you know that anchor, your easy Zone 2 sits clearly below it. This anchor comes from your real effort, not your age.

The third is the drift check. On a long, flat, easy run, watch how your heart rate moves while your pace stays steady. If your heart rate climbs more than about 5 percent over the run, you started too hard for true Zone 2. A small drift means the effort was truly aerobic. Run this check every few weeks to keep yourself honest.

These checks are not a downgrade from heart rate. In the 165-runner study, simple effort-based methods like the talk test held up as well as fixed heart rate targets for finding the right intensity (Nuuttila et al., 2025). Your body is a better guide than the chart. The chart just gives you a place to begin.

Why does PIRX project your race time when a zone cannot?

A Zone 2 heart rate controls your effort today. It cannot tell you how fast you will race. Two runners can both log clean Zone 2 work and still finish a 10K minutes apart. The zone is an input, not an answer.

Your easy Zone 2 volume feeds one part of your fitness, called your Aerobic Base. That is the engine you grow from steady easy miles. But a base alone does not set a finish time. Four other parts of your fitness pull on the result too.

This is the gap PIRX fills. PIRX is a proprietary machine-learning prediction engine. It does not lean on your age or one fixed number. It reads your real runs. From that data it scores five drivers: Aerobic Base, Threshold Density, Speed Exposure, Load Consistency, and Running Economy. Those five drivers add up to your improvement, measured in seconds. Not a vague percent. Real seconds you can see.

PIRX then gives you a Projected Time with a Supported Range, which is the spread of likely finish times for your current fitness. It recalculates after every synced activity. A visible change in your Projected Time shows only when the structural change is at least 2 seconds. So you see real progress, not the daily noise a heart rate reading alone would feed you. If you are new here, start with the complete guide to predicting your race time.

98%

validated prediction accuracy (PIRX users)

Find your real Zone 2, then see your projected time

The by-age chart is a fine place to start. It gives you a number on day one. But your true Zone 2 can sit well off the chart, and only a field test pins it down. Use the talk test, a threshold check, and a drift check to make the zone your own.

Then go one step further. A zone cannot tell you what you will run on race day. PIRX can. Connect your Garmin, COROS, or Strava in under a minute. PIRX reads your runs and projects your race time, with the seconds each driver adds or takes away. One-size-fits-all formulas treat every runner the same. PIRX does not. It learns from your data. Free, no signup, no lab needed.

Sources

• Maffetone, P. & Laursen, P.B. (2020). Maximum Aerobic Function: Clinical Relevance, Physiological Underpinnings, and Practical Application. Frontiers in Physiology, 11, 296. (The 180-Formula sets a 10-beat aerobic band, far tighter than the 40-plus-beat spread of a percent-of-max range; neither the 180 nor 220 formula replaces lab testing for the aerobic threshold.)
• Davis, J. (2025). Individual variation in heart rates at LT1 and LT2 in runners. Running Writings. (A synthesis of seven studies on 140 runners found the Zone 2 ceiling, LT1, can fall anywhere from 69 to 94 percent of max heart rate.)
• Nuuttila, O.P. et al. (2025). The accuracy of fixed intensity anchors to estimate lactate thresholds in recreational runners. European Journal of Applied Physiology, 125, 2161-2171. (In 165 recreational runners, effort had to stay at or under 70 percent of max heart rate to keep everyone below the first threshold; no single fixed heart rate fit all, and effort-based methods performed as well as fixed targets.)