Heart Rate Zone Calculator
Five training zones from your max heart rate
Enter your max heart rate to get your five training zones. Don’t know your max? Flip the switch and answer three quick questions for a research-backed estimate.
Max heart rate
Use the highest heart rate you’ve seen on a monitor during an all-out effort.
Estimate your max heart rate
Enter your age to get an estimate.
Your training zones
How to use this heart rate zone calculator
Type your max heart rate into the box and your five zones appear instantly, in beats per minute. The table is built to fit on one phone screen, so athletes can screenshot it and keep it handy during workouts. If you don't know your max heart rate, turn on I don't know. You'll answer three quick questions, and the calculator fills in an estimate and builds your zones from it.
The five heart rate training zones
This calculator uses the traditional five-zone model, where each zone is a 10% band of your max heart rate. It's the most widely used zone system in fitness and coaching, and it's what most heart rate monitors and fitness apps show by default.
| Zone | % of max HR | What it trains | CrossFit use |
|---|---|---|---|
| Zone 1: Recovery | 50–60% | Blood flow and recovery | Warm-ups, cooldowns, flush pieces |
| Zone 2: Aerobic base | 60–70% | Aerobic engine and fat use | Long, easy monostructural work at a conversational pace |
| Zone 3: Tempo | 70–80% | Aerobic power and pacing | Longer steady pieces and moderate metcons |
| Zone 4: Threshold | 80–90% | Lactate threshold | Hard intervals and competition-pace efforts |
| Zone 5: Max | 90–100% | Top-end speed and power | Sprints and short all-out efforts |
Each zone's range runs from its lower percentage up to one beat below the next zone, so no heart rate falls into two zones. Zone 5 runs right up to your max.
How the max heart rate estimate works
Your zones are only as accurate as the max heart rate they're built on, so we reviewed more than a dozen studies comparing max heart rate equations against lab-measured values before choosing one. Here's what we use and why.
We use the Tanaka formula: 208 − 0.7 × age
The Tanaka equation comes from a 2001 meta-analysis of 351 studies covering 18,712 people, confirmed in a lab study of 514 healthy adults. In later head-to-head comparisons it has consistently been the most accurate or close to it, including a 2020 study of treadmill tests in adults (Shookster et al.), a 2025 comparison published in PLoS One (Martin et al.), and studies of trained endurance athletes (Lach et al. 2021; Kasiak et al. 2023). The Gellish formula (207 − 0.7 × age) gives nearly identical numbers and backs it up.
Why not 220 − age?
The classic 220 − age formula was never based on a formal study. It overestimates max heart rate in younger athletes and underestimates it in older athletes, by up to about 9 bpm. For a 60-year-old masters athlete, it can push every zone too low.
| Age | 20 | 30 | 40 | 50 | 60 |
|---|---|---|---|---|---|
| Tanaka (used here) | 194 | 187 | 180 | 173 | 166 |
| 220 − age | 200 | 190 | 180 | 170 | 160 |
| HUNT / Nes (211 − 0.64 × age) | 198 | 192 | 185 | 179 | 173 |
Why there's no adjustment for sex or fitness
We tested the main alternatives. The HUNT formula (Nes et al. 2013) tends to run about 4–6 bpm high in other groups. The Gulati formula for women (206 − 0.88 × age) overestimated max heart rate by about 8 bpm in fit women in a later study. Across the research, separate equations for men, women or fitness levels didn't predict better than Tanaka, so we use one equation for everyone.
Why bike training lowers the estimate
Max heart rate depends partly on how much muscle is working. Studies comparing the same athletes on different machines find cycling max heart rate is typically 2–6 bpm lower than running, while rowing is close to running (Faff et al. 2007). If you mostly train on a bike or air bike, we subtract 4 bpm. Mixed CrossFit training and rowing use the standard estimate.
Your recorded peak overrides the formula
Every formula has an individual error of about ±10 bpm, and some athletes are 20 bpm or more away from their age-predicted value. A heart rate you've actually reached is real evidence, so if the highest heart rate you've seen is above the formula estimate, the calculator uses your peak instead. A recent field study of endurance athletes found formulas tended to underestimate their real peaks by around 5 bpm, which is another reason to trust a measured number.
How to find your true max heart rate
A formula is a starting point. To get your real number, wear a chest-strap monitor (wrist sensors often lag during hard efforts) and look at your highest reading after one of these:
- Run or row test: warm up for 15 minutes, then go hard for 3 minutes, recover for 2–3 minutes, and finish with an all-out 2–3 minute effort.
- Hill repeats: 3 × 2 minutes uphill at maximum effort, jogging back down between efforts.
- Your hardest recent efforts: check your monitor data from the end of a race, a 2K row or a brutal sprint finish.
Only test if you're healthy and used to hard training. If you have a heart condition, take medication that affects heart rate (such as beta blockers), or are new to exercise, talk to your doctor before any max effort, and use their guidance for your zones.
Want your conditioning programmed for you? ZOAR Fitness coaches build zone-based engine work into every training plan, from first-time CrossFitters to competitive athletes.
Train with ZOARFrequently asked questions
What is the most accurate max heart rate formula?
Across the studies we reviewed, Tanaka's 208 − 0.7 × age is the most consistently accurate formula for healthy adults and trained athletes. Even so, it's usually within about 10 bpm of a person's real max, not exact. A measured max from a hard effort is always better.
What heart rate zone should most training be in?
Many coaches build a large share of conditioning volume in Zone 2 to develop the aerobic base, with smaller amounts of hard Zone 4–5 work. In CrossFit, most metcons will push you into Zones 4 and 5, so dedicated easy Zone 2 sessions on a rower, bike or run help balance that out.
Why is my heart rate higher on the rower than the bike?
Rowing and running use more muscle than cycling, which drives heart rate higher. Many athletes see a max on the bike that's a few beats lower than on the rower or treadmill. If you train mostly on a bike, use a max heart rate measured on the bike.
Does max heart rate go down with fitness?
Max heart rate mainly declines with age and changes very little with training. What fitness changes is your resting heart rate and how much work you can do at a given heart rate. A lower max heart rate doesn't mean you're less fit.
Why does my watch show different zones?
Many devices use 220 − age, a different zone model, or zones based on heart rate reserve or lactate threshold. Enter the same max heart rate into your device and this calculator, and set your device to percent of max heart rate, so your zones match.
Sources
- Tanaka H, Monahan KD, Seals DR. J Am Coll Cardiol, 2001. Link
- Gellish RL, et al. Med Sci Sports Exerc, 2007. Link
- Nes BM, et al. (HUNT Fitness Study). Scand J Med Sci Sports, 2013. Link
- Gulati M, et al. Circulation, 2010. Link
- Shookster D, et al. Int J Exerc Sci, 2020. Link
- Martin et al. PLoS One, 2025. Link
- Lach J, et al. Frontiers in Physiology, 2021. Link
- Kasiak P, et al. Preprint, 2023. Link
- Price KJ, et al. Int J Environ Res Public Health, 2022. Link
- Faff J, et al. 2007. Link
- Cleary MA, et al. 2011. Link
- Sarzynski MA, et al. (HERITAGE Family Study), 2013.
- Whyte GP, et al. Int J Sports Med, 2008.
This calculator is for general training guidance and isn't medical advice. Built by ZOAR Fitness. More free tools for athletes and coaches at zoarfitness.com/tools.