Free calculator
Heart Rate Zone Calculator
Written by the GymStreak coaching teamUpdated
If you know your real maximum from a hard test or race, enter it. It beats any age formula.
The short answer
Heart rate zones are ranges of beats per minute that match different training intensities. The simplest way to find them is to estimate your maximum heart rate as 220 minus your age and take percentages of it; the Karvonen method is more personal because it also uses your resting heart rate. For a 30-year-old with a resting heart rate of 60, zone 2 is about 138 to 151 bpm.
01 / How it works
How the heart rate zone calculator works
Every zone is a slice between your resting and your maximum heart rate. To work them out you need an estimate of your maximum heart rate (HRmax). The calculator offers the classic 220 − age and the Tanaka formula, 208 − 0.7 × age, which was built from a much larger pool of data and reads a little higher for older adults. If you have seen a higher number on a heart-rate strap during an all-out effort, enter it instead: a measured maximum beats any formula.
Then choose a method. % of max simply multiplies your maximum by 50%, 60%, 70% and so on. Heart rate reserve (Karvonen) first subtracts your resting heart rate from your maximum, takes the percentage of that reserve, and adds the resting rate back. Because it accounts for how fit your heart already is, it gives higher, more personal zones, and it lines up better with the percentage of oxygen uptake you are actually using.
The calculator uses a common five-zone model in 10% steps, from very light (zone 1) to maximum (zone 5). Watches and apps sometimes use slightly different cut-offs, so your zones may not match your device exactly.
02 / Formula
The heart rate zone formulas
Maximum heart rate
Fox: HRmax = 220 − age Tanaka: HRmax = 208 − 0.7 × age
Both estimate an average for people of your age. The typical error of 220 − age is about 7 to 11 beats per minute, and some people differ by much more.
Karvonen formula (heart rate reserve)
Target HR = (HRmax − HRrest) × intensity + HRrest
- HRmax − HRrest = heart rate reserve (HRR)
- intensity = 0.5 to 1.0 (50% to 100%)
- HRrest = resting heart rate, measured in the morning before getting up
Percentage of maximum heart rate
Target HR = HRmax × intensity
03 / Worked example
Worked example
Zone 2 for a 30-year-old with a resting heart rate of 60
Using 220 − age for the maximum and the Karvonen method.
- 1HRmax = 220 − 30 = 190 bpm
- 2Reserve = 190 − 60 = 130 bpm
- 3Zone 2 low = 130 × 0.60 + 60 = 138 bpm
- 4Zone 2 high = 130 × 0.70 + 60 = 151 bpm
Zone 2 is 138–151 bpm. With the simpler % of max method it would be 114–133 bpm, which is why the two methods feel so different on an easy run.
04 / Reference
Heart rate zone charts and tables
| Zone | Intensity | Karvonen (bpm) | % of max (bpm) | How it feels |
|---|---|---|---|---|
| 1 · Very light | 50–60% | 125–138 | 95–114 | Easy breathing, warm-up pace |
| 2 · Light | 60–70% | 138–151 | 114–133 | Full conversation possible |
| 3 · Moderate | 70–80% | 151–164 | 133–152 | Short sentences only |
| 4 · Hard | 80–90% | 164–177 | 152–171 | A few words at a time |
| 5 · Maximum | 90–100% | 177–190 | 171–190 | Can’t talk; seconds to minutes |
| Age | 220 − age | Tanaka (208 − 0.7 × age) |
|---|---|---|
| 20 | 200 | 194 |
| 30 | 190 | 187 |
| 40 | 180 | 180 |
| 50 | 170 | 173 |
| 60 | 160 | 166 |
| 70 | 150 | 159 |
| Intensity | % heart rate reserve | % max heart rate |
|---|---|---|
| Very light | Under 30% | Under 57% |
| Light | 30–39% | 57–63% |
| Moderate | 40–59% | 64–76% |
| Vigorous | 60–89% | 77–95% |
| Near-maximal to maximal | 90% or more | 96% or more |
Guidelines for adults call for at least 150 minutes a week of moderate or 75 minutes of vigorous aerobic activity (or a mix). This table shows where those intensities fall.
Source: American College of Sports Medicine. ACSM’s Guidelines for Exercise Testing and Prescription. 11th ed. Wolters Kluwer; 2021.
05 / Training
How to train with your heart rate zones
- Spend most of your cardio time easy. Zone 2 work builds your aerobic base and is easy to recover from. Many endurance programmes keep the majority of weekly minutes in zones 1–2 and a smaller share hard.
- Add one or two harder sessions a week in zones 4–5, such as intervals on the treadmill, rowing machine or spin bike. These do the most for your VO2 max.
- Use the talk test as a check. If you can chat, you are in zone 1–2; short sentences, zone 3; a few words, zone 4 or above.
- Keep cardio and lifting from clashing. Easy zone 2 sessions interfere least with strength gains. See how to minimise cardio and strength training interference and HIIT vs steady-state cardio.
- Wrist-based heart rate can lag behind during intervals. A chest strap is more accurate for short, hard efforts.
06 / Limitations
Limitations and safety
Age formulas estimate an average maximum. Your real maximum can easily be 10 or more beats higher or lower, which shifts every zone. A measured maximum from a hard, supervised test is better.
Some medicines, especially beta blockers, lower heart rate and make heart-rate zones unreliable. Heat, dehydration, caffeine, stress and poor sleep also push heart rate up.
If you have a heart condition or feel chest pain, dizziness or unusual breathlessness during exercise, stop and get medical advice.
This calculator gives an estimate for general fitness education. It is not medical advice and does not diagnose anything. If you have a health condition, are pregnant, or are new to hard exercise, check with a doctor first.
07 / FAQ
Frequently asked questions
How do I calculate my heart rate zones by age?
Estimate your maximum heart rate as 220 minus your age (or 208 − 0.7 × age), then take 50–60%, 60–70%, 70–80%, 80–90% and 90–100% of it for zones 1 to 5. For more personal zones, use the Karvonen method, which also uses your resting heart rate.
What is zone 2 heart rate?
Zone 2 is light, steady aerobic exercise at about 60–70% of your heart rate reserve or maximum heart rate, where you can still hold a conversation. For a 30-year-old with a resting heart rate of 60 it is about 138–151 bpm with the Karvonen method.
What is the Karvonen formula?
The Karvonen formula sets target heart rate as (maximum heart rate − resting heart rate) × intensity + resting heart rate. The part in brackets is your heart rate reserve. It gives more personal zones than a straight percentage of maximum.
Is 220 minus age accurate?
It is a rough average with a typical error of about 7 to 11 bpm, and some people differ by more. The Tanaka formula (208 − 0.7 × age) fits large data sets better, especially for older adults. If you know your real maximum from a hard effort, use that.
Which heart rate zone burns the most fat?
Lower zones use a higher share of fat for fuel, but harder sessions burn more total calories per minute. For fat loss, total weekly activity and your diet matter far more than the zone. Our TDEE calculator helps with the diet side.
How do I measure my resting heart rate?
Take your pulse for 60 seconds (or 30 seconds × 2) in the morning after waking, before you get up or have caffeine. Do it on three mornings and use the average. Many watches also report it.
Should I use heart rate reserve or % of max heart rate?
Heart rate reserve (Karvonen) is usually better for training because it accounts for your resting heart rate and fitness. % of max is simpler and fine if you do not know your resting heart rate; just expect lower numbers for each zone.
Sources
- Karvonen MJ, Kentala E, Mustala O. The effects of training on heart rate; a longitudinal study. Ann Med Exp Biol Fenn. 1957;35(3):307-315.
- Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol. 2001;37(1):153-156.
- Robergs RA, Landwehr R. The surprising history of the "HRmax = 220 − age" equation. J Exerc Physiol Online. 2002;5(2):1-10.
- Fox SM 3rd, Naughton JP, Haskell WL. Physical activity and the prevention of coronary heart disease. Ann Clin Res. 1971;3(6):404-432.
- American College of Sports Medicine. ACSM’s Guidelines for Exercise Testing and Prescription. 11th ed. Philadelphia: Wolters Kluwer; 2021.
- U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition. 2018.
Related tools
- VO2 Max CalculatorEstimate VO2 max from the Cooper 12-minute run, the Rockport 1-mile walk or your resting heart rate, with norms by age.
- TDEE CalculatorEstimate the calories you burn per day, then get a target for losing, keeping or gaining weight.
- One Rep Max CalculatorEstimate your 1RM from any set of 1–12 reps and get training loads for every percentage.
From the blog
Exercises to try
- TreadmillBeginner cardio on the treadmill, for heart and lung fitness.
- RowingBeginner cardio on the rowing machine, for heart and lung fitness.
- Spin BikeBeginner cardio on the spin bike, for heart and lung fitness.
- EllipticalBeginner cardio on the elliptical machine, for heart and lung fitness.
- StairmasterBeginner cardio on the stairmaster, for heart and lung fitness.
Put your zones into a weekly plan
GymStreak builds workouts around your goal and schedule, and syncs workouts and energy with Apple Health and Health Connect.
