Hub · heart-rate models
Heart Rate Training Zones
Every heart-rate zone model in one place: max heart rate, %HRmax 5-zone, Karvonen heart-rate reserve, MAF 180 and LTHR threshold zones. Free, no signup.
Max Heart Rate Calculator
Your maximum heart rate is the highest your heart can beat at all-out effort. Age formulas estimate it: Tanaka gives 208 − 0.7 × age, the classic 220 − age runs high. At age 35 that is 184 and 185 bpm, but true values vary by ±10–12 bpm, so test it.
Heart Rate Zone Calculator
Heart-rate zones are percentages of your maximum heart rate: Zone 1 is 50–60%, Zone 2 60–70%, Zone 3 70–80%, Zone 4 80–90% and Zone 5 90–100%. At a max of 185 bpm, Zone 2, the aerobic-base zone, is 111–130 bpm. Most easy training belongs in Zones 1–2.
Target Heart Rate Calculator
Your target heart rate for moderate exercise is 64 to 76% of your maximum heart rate, and 77 to 93% for vigorous exercise, with the maximum taken as 220 minus your age. For a 50-year-old that is 109 to 129 bpm moderate and 131 to 158 bpm vigorous. The American Heart Association draws the same bands lower, at 50 to 70% and 70 to 85%.
Fat Burning Zone Calculator
Fat oxidation peaks at roughly 74% of your maximum heart rate, not in the low band most gym equipment labels fat burn. For a 190 bpm maximum that is about 141 bpm, with fat oxidation staying near its peak from 129 to 150 bpm. Below that you burn a higher percentage of fat but fewer fat grams per minute.
Karvonen Heart Rate Reserve Calculator
The Karvonen formula sets zones from your heart-rate reserve: maximum minus resting heart rate. Target = intensity% × (HRmax − RHR) + RHR. With a max of 185 and resting of 50 bpm (reserve 135), 70% gives 0.70 × 135 + 50 ≈ 145 bpm. The zones follow your fitness.
MAF 180 Formula Calculator
Maffetone's 180 Formula sets your maximum aerobic heart rate at 180 minus your age, adjusted for health and training status. A consistent, injury-free 35-year-old gets 180 − 35 = 145 bpm and an aerobic range of 135–145 bpm. Train at or below it to build the aerobic base.
Friel LTHR Heart Rate Zone Calculator
Joe Friel's heart-rate zones anchor to your lactate-threshold heart rate (LTHR) instead of an age-estimated maximum. Zone 5 splits into 5a, 5b and 5c, so the 5-zone model is usually shown as 7. Threshold (Zone 4) is 94–99% of LTHR for cycling, 95–99% for running. Find LTHR from the last 20 minutes of a 30-minute time trial.
Rowing Heart Rate Zones (UT2–AN)
Rowing uses a five-band heart-rate model: UT2 is 55–70% of maximum, UT1 70–80%, AT 80–85%, TR 85–95% and AN above 95%. At a 190 bpm maximum, UT2 is 105–133 bpm and threshold AT 152–162 bpm. Most rowing volume should be steady UT2.
XC Skiing & Biathlon Heart Rate Zones (I1–I5)
Cross-country skiing and biathlon use the Norwegian/FIS I1–I5 scale: I1 is 60–72% of maximum heart rate (<2 mmol/L lactate), I2 72–82% (~2), I3 82–87% (2.5–4), I4 87–92% (4–6) and I5 92–100% (>6). At 190 bpm maximum, I1 is 114–137 bpm and I3 156–165 bpm.
Ski Mountaineering Vertical Calculator
Ski-mountaineering is decided on the climbs, so vertical ascent rate (Vm/h) is the key anchor alongside 5-zone heart rate. VAM is vertical meters divided by hours: 600 m in 30 minutes is 1,200 m/h. Pace long climbs at 70–95% of test VAM, 840–1,140 m/h here.
Which heart-rate model should you use?
Every model below slices the same intensity spectrum. What separates them is the anchor they measure from, and an anchor you have actually tested beats a better model built on a guess.
| Model | Anchored to | Best for | You need |
|---|---|---|---|
| Max Heart Rate | Age, or a measured maximum | A first estimate when you have no test data at all | Your age. A measured HRmax is far better. |
| HR Zones (%HRmax) | Percentages of HRmax | Everyday training once you know your maximum | Max heart rate |
| Karvonen (HRR) | Heart-rate reserve, max minus resting | Trained athletes, whose low resting rate makes plain %HRmax read too easy | Max and resting heart rate |
| MAF 180 | 180 minus age, adjusted for health | Aerobic base blocks, and athletes returning from illness or injury | Your age, and an honest health adjustment |
| LTHR Zones | Lactate-threshold heart rate | The most accurate zones, once you can run a threshold test | LTHR from a 30-minute time trial |
Swipe sideways for every column. Pick the lowest row you have real data for.
The anchor matters more than the model
Every heart-rate zone system is a set of percentages applied to one number. Get that number wrong and every zone moves with it, no matter which model you picked. A 20 bpm error in your assumed maximum shifts each boundary by roughly the same proportion, which is enough to turn an easy run into a tempo run on paper.
This is why age-based formulas are a starting point rather than an answer. Tanaka's 208 minus 0.7 times age has a standard deviation of about 10 bpm across a population, so for any individual it can easily be off by more. If you can test, test. If you cannot, use the estimate and adjust it the first time you see a higher number in a hard session.
Heart rate lags, and that is fine
Heart rate is a response, not a command. It takes 30 to 90 seconds to catch up with a change in effort, and it drifts upward over a long session at fixed output as you fatigue and lose fluid. Neither is a fault in the number, it is what a physiological signal does.
The practical consequence is where to trust it. For long aerobic work heart rate is an excellent guide, because there is time for it to settle. For short intervals it is a poor one: a 40-second effort is over before your heart rate arrives. Use power or pace there, and treat heart rate as a record of what the session cost rather than a target to chase.
Frequently asked questions
What is the most accurate heart-rate zone model?
Zones anchored to lactate-threshold heart rate are the most accurate, because LTHR is measured directly from a time trial rather than estimated from age. Karvonen comes next as it accounts for your resting heart rate. Age-based %HRmax is the least precise, though it is the only option when you have no test data.
Should I use max heart rate or threshold heart rate?
Use threshold heart rate if you have tested it. LTHR sits near the intensity you actually train around, so zones built from it track your fitness as it changes. Max heart rate barely moves with training and is harder to measure honestly, since reaching a true maximum requires an all-out effort most athletes never quite produce.
Why do my zones differ between Garmin, Strava and this site?
Because each platform anchors zones to a different marker and numbers them differently. One may use %HRmax, another heart-rate reserve, another your threshold. Zones only line up across apps when the anchor and the model match, so set the anchor deliberately rather than accepting a default.
How many heart-rate zones should I use?
Five is the common default and is enough for most athletes. Three-zone polarized models are simpler to train by and make the easy-hard split obvious, while seven-zone systems give finer control near threshold. All of them divide the same spectrum, so the count matters far less than the anchor underneath it.
- What Heart Rate Zone Should You Train In?Which heart-rate zone to train in and when: most time easy in Zone 2, a controlled dose at threshold, a little in Zone 5. Plus how to find your zones.
- Zone 2 Heart Rate, ExplainedWhat Zone 2 training is, why it builds your aerobic base, how to find your own Zone 2 heart rate with the talk test, LT1 or MAF, and how much of it to do.
- How Every Watch Calculates Your Max Heart Rate (10 Brands Compared)Garmin uses Tanaka, COROS uses Gellish, Apple publishes nothing, Wahoo skips HRmax entirely. Ten brands, their formulas and zone models, in one table.