Maximum Heart Rate Calculator
Estimate your maximum heart rate from age using the standard HRmax = 220 − age formula — with the option to compare five evidence-based equations, solve for age from a known HRmax, and read off the five standard training zones in beats per minute.
The 220 − age formula is a rough rule of thumb
The Fox equation was not derived from a controlled study — it is a regression line informally fitted to data from about 11 earlier studies, some of which did not actually measure HRmax directly. Its standard error is ±10–12 bpm, meaning about a third of people have a true HRmax more than 10 bpm away from the prediction. For clinical use and for precision training zones, a measured HRmax (from a graded exercise test) is far better. Still, the formula remains the standard shorthand because it is easy to remember and only needs age.
HRmax declines with age — but not by exactly 1 bpm per year
The 220 − age formula assumes a perfectly linear decline of 1 bpm per year, which comes from an intercept of 220 and a slope of −1. Modern studies show that HRmax declines more slowly than that — the slope is closer to −0.64 bpm/year in the HUNT study (211 − 0.64·age) and −0.7 bpm/year in Tanaka's meta-analysis (208 − 0.7·age). The practical effect is that 220 − age under-predicts HRmax in older adults (who can often reach higher rates than the formula suggests) and over-predicts in younger adults (whose true HRmax is often lower).
Training does not change HRmax — but it changes everything else
Endurance training lowers resting heart rate and increases stroke volume, so the same cardiac output is achieved at a lower rate. But HRmax itself stays essentially fixed — a 40-year-old marathoner and a 40-year-old sedentary adult have similar HRmax values. What changes is the percentage of HRmax at which the lactate threshold and aerobic ceiling occur: a trained athlete can sustain 85% of HRmax for an hour, while an untrained person might only manage 65%. This is why training zones are calibrated to individual threshold data, not to HRmax alone.
HRmax is a ceiling, not a target
Maximum heart rate is the highest rate the heart can reach during all-out effort — it is a diagnostic number, not a training intensity. Most training should happen well below HRmax: easy aerobic work sits at 60–75%, tempo work at 80–88%, and only short intervals approach 90–95%. Sustained work above 95% of HRmax is not sustainable and, in people with undiagnosed cardiac conditions, carries real risk. The five-zone model above shows the standard training bands; consult a physician before starting vigorous exercise if you have cardiovascular risk factors.
How to Use This Calculator
The maximum heart rate estimate needs only your age, and everything else — training zones, heart-rate reserve, Karvonen targets — follows from it. Pick a formula, enter your age, and read the zones.
1. Pick an estimation formula
The Standard Fox equation (220 − age) is the default. For more accuracy, choose Tanaka, Nes/HUNT, or Oakland. Women may prefer the Gulati equation, which was derived specifically from female cohorts.
2. Enter your age
Age in years is the only required input. If you already know your HRmax from a lab test, switch the "Solve for" toggle to Age and the calculator will back out the age that matches.
3. Add resting heart rate (optional)
Resting HR lets the calculator compute Karvonen targets, which use heart-rate reserve (HRmax − RHR) rather than HRmax alone. It makes zones more personal, especially for trained athletes with low resting HR.
4. Read the result and zone strip
The result card shows your HRmax and the five training zones in bpm, colour-coded from recovery (Zone 1) to maximum (Zone 5). Each zone shows its % range and bpm band.
5. Compare formulas on the chart
The HRmax vs. age chart plots all five equations so you can see how much they diverge at your age — and which one gives the most conservative or most aggressive estimate.
6. Switch to Advanced for depth
Advanced mode adds a Karvonen target chart, a sensitivity check on how HRmax changes with age, and companion metrics including heart-rate reserve, aerobic threshold estimate, and percentage-of-max calculations.
What This Tool Offers
Built around the standard HRmax = 220 − age formula, with modern alternatives and full training-zone readouts.
Two-way solving
Solve for maximum heart rate given age, or for age given a known HRmax. The calculator inverts whichever formula you have selected.
Five estimation formulas
Standard Fox (220 − age), Tanaka (208 − 0.7·age), Gulati (206 − 0.88·age, women), Nes/HUNT (211 − 0.64·age), and Oakland (200 − 0.48·age).
Five training zones
Zone 1 (50–60%) through Zone 5 (90–100%), each shown in bpm and colour-coded, both as a strip on the result card and as a chart.
Karvonen targets
Optional resting HR input unlocks heart-rate reserve and Karvonen targets, which personalise zones for athletes with low resting heart rates.
Formula comparison chart
A single chart plotting all five equations across the age range, with your current point highlighted — so you can see exactly how much the choice of formula matters.
Reference tables
A full HRmax lookup grid by age and formula, a training-zone reference table, a percentage-of-max conversion chart, and a complete variable reference.
Reference Tables & Conversions
A percentage-of-max converter, an HRmax lookup grid across all five formulas, and a training-zone reference table.
Percentage-of-max heart rate converter
HRmax Lookup by Age and Formula
Age-predicted maximum heart rate in bpm across all five formulas.
| Age (yr) | Fox 220−age | Tanaka 208−0.7·age | Gulati 206−0.88·age | Nes 211−0.64·age | Oakland 200−0.48·age | Spread |
|---|
Training Zones at Current HRmax
The five standard training zones with % ranges, bpm boundaries (Karvonen using heart-rate reserve), and physiological descriptions.
| Zone | % HRmax | % HRR | Karvonen bpm | % of HRmax bpm | Physiological description |
|---|
Variable Reference
| Symbol | Meaning | Typical range | Units |
|---|---|---|---|
| HRmax | Maximum heart rate | 150 – 220 | bpm |
| Age | Age in years | 5 – 100 | years |
| RHR | Resting heart rate | 40 – 100 | bpm |
| HRR | Heart-rate reserve (HRmax − RHR) | 60 – 160 | bpm |
| Z1 | Zone 1 — recovery | 50 – 60% HRmax | bpm |
| Z2 | Zone 2 — fat burn / aerobic | 60 – 70% HRmax | bpm |
| Z3 | Zone 3 — aerobic / cardio | 70 – 80% HRmax | bpm |
| Z4 | Zone 4 — anaerobic / threshold | 80 – 90% HRmax | bpm |
| Z5 | Zone 5 — maximum | 90 – 100% HRmax | bpm |
What Does HRmax = 220 − Age Measure?
Maximum heart rate is the highest rate your heart can beat during all-out effort. It is a physiological ceiling set mainly by genetics and age, and it declines slowly as you get older — roughly 0.5 to 1 beat per minute per year across the adult lifespan. The standard 220 − age formula is the simplest way to estimate it, requiring only your age. It is not precise: individual values can vary by ±10–15 bpm from the prediction, which is why measured HRmax from a graded exercise test is always preferable when precision matters, and why training zones should be treated as guidelines rather than hard boundaries.
Maximum Heart Rate Formula
The standard Fox equation (1971) is a single linear expression:
where age is in years and HRmax is in beats per minute. Modern alternatives use different intercepts and slopes:
Gulati (2010, women): HRmax = 206 − 0.88·age
Nes / HUNT (2013): HRmax = 211 − 0.64·age
Oakland (2015): HRmax = 200 − 0.48·age
Training zones are typically defined as percentages of HRmax, or — more accurately — as percentages of heart-rate reserve (HRR):
Karvonen target = (HRR × %Intensity) + RHR
Maximum Heart Rate Variables
| Symbol | Meaning | Notes |
|---|---|---|
| HRmax | Maximum heart rate | Highest achievable rate during all-out effort; bpm |
| Age | Age in years | The only input needed for the standard formula |
| RHR | Resting heart rate | Measured on waking; 40–100 bpm for healthy adults |
| HRR | Heart-rate reserve | HRmax − RHR; the range available for exercise |
| %HRmax | Percentage of maximum | Simpler but less personal than %HRR |
| %HRR | Percentage of reserve | Karvonen method; more accurate for trained athletes |
| Z1–Z5 | Training zones | Five bands from 50% to 100% of HRmax |
How Age Affects HRmax
Every formula for HRmax has a negative slope in age, but they disagree on how steep it is. The standard Fox equation drops 1 bpm per year. Tanaka and Gulati use slopes of −0.7 and −0.88. Nes and Oakland use gentler slopes of −0.64 and −0.48, so they predict higher HRmax values in older adults. The practical consequence: at age 20 the five formulas span about 12 bpm, and at age 70 they span about 25 bpm. This is why the choice of formula matters more the older you get, and why a single formula should never be treated as ground truth.
Individual variation within a single age is even larger than the spread between formulas. Two 40-year-olds of similar fitness can have HRmax values 20 bpm apart, and neither is unusual. Genetics, heart size, and autonomic tone all contribute. If you train seriously, the gold standard is to measure HRmax in a supervised graded exercise test or a well-executed field test — a 5-minute all-out effort after a thorough warm-up, followed by a sprint to exhaustion. Even then, measurement error of ±3–5 bpm is normal.
Maximum Heart Rate Examples
HRmax = 220 − 35 = 185 bpm
HRmax = 208 − 0.7 × 35 = 208 − 24.5 = 183.5 bpm
HRmax = 211 − 0.64 × 35 = 211 − 22.4 = 188.6 bpm
age = 220 − 185 = 35 years
HRR = 185 − 60 = 125 bpm
Target = 0.70 × 125 + 60 = 147.5 bpm
Frequently Asked Questions
The 220 − age formula is a rough rule of thumb with a standard error of about ±10–12 bpm, meaning roughly a third of people have a true HRmax more than 10 bpm away from the prediction. It also systematically over-predicts HRmax in young adults and under-predicts it in older adults, because the true decline is closer to 0.6–0.7 bpm per year rather than 1 bpm per year. It remains widely used because it is simple and needs only age, but for serious training or clinical purposes, a measured HRmax from a graded exercise test is far more reliable.
No. Endurance training markedly lowers resting heart rate and increases stroke volume, so the same cardiac output is achieved at a lower rate — but HRmax itself stays essentially unchanged. A 40-year-old marathoner and a 40-year-old sedentary adult have similar HRmax values. What changes with training is the fraction of HRmax you can sustain: a trained athlete might hold 85% of HRmax for an hour, while an untrained person reaches their limit at 65%. This is why zones based on %HRmax alone are less useful for athletes than zones based on measured lactate threshold or %HRR.
If you want the simplest answer, use the standard Fox equation (220 − age). For most adults, Tanaka (208 − 0.7·age) is a reasonable upgrade — it was derived from a meta-analysis of 351 studies and has a smaller standard error. Women may prefer Gulati (206 − 0.88·age), which was derived specifically from a cohort of over 5,000 women. The Nes/HUNT equation (211 − 0.64·age) is well-validated in large Scandinavian cohorts and predicts higher HRmax in older adults. Oakland (200 − 0.48·age) is the most conservative. The truth is that no formula is precise for any individual — the differences between them are smaller than the within-age variation between people.
The Karvonen method computes target heart rate as a percentage of heart-rate reserve (HRmax − resting HR) rather than as a percentage of HRmax alone. The formula is: target = (HRR × %intensity) + RHR. It is more personal because it accounts for the fact that people with low resting heart rates have a larger usable range between rest and maximum. For example, at 70% intensity, the simple %HRmax method gives 130 bpm for an HRmax of 185, while Karvonen with RHR = 60 gives 147.5 bpm. The gap grows for fitter individuals, which is why Karvonen is the preferred method for trained athletes.
The gold standard is a supervised graded exercise test in a sports medicine lab, with ECG monitoring and a physician present. Field tests are cheaper but less safe: the classic protocol is a thorough 15-minute warm-up, then a series of 3-minute hard efforts with 3-minute recoveries, then a final all-out effort to exhaustion. The highest rate reached is your HRmax. Field tests carry real cardiac risk, especially for men over 40, women over 50, and anyone with cardiovascular risk factors, and should not be attempted without medical clearance. For most recreational athletes, the age-predicted value plus 10–12 bpm is a safer working ceiling.
Zone 2 (60–70% of HRmax) does burn a higher proportion of calories from fat than higher zones, but the absolute number of fat calories burned is often lower than at moderate intensities, because the total energy expenditure is lower. What Zone 2 does exceptionally well is build aerobic base — mitochondrial density, capillary networks, fat-oxidation enzymes — without accumulating fatigue. Most endurance athletes spend 70–80% of their training time in Zone 2 for exactly this reason. For fat loss specifically, total calorie deficit matters far more than which zone the exercise is performed in.
Yes, but only roughly. The most common approach uses the Keytel equation, which estimates energy expenditure from heart rate, age, weight, sex and exercise duration. It is accurate to about ±15–20% for steady-state aerobic exercise. Wearable devices that estimate calorie burn from heart rate use similar equations with proprietary corrections. The estimate is better for moderate-intensity work and worse at very high or very low intensities, and it degrades in heat, at altitude, and during interval training. For most people, a heart-rate-based calorie estimate is good enough for tracking trends, but not for precise nutrition planning.
Variables
| Symbol | Quantity | Unit |
|---|---|---|
| HRmax | Estimated maximum heart rate | bpm |
| age | Age | years |
What it means
The formula HRmax = 220 – age is a widely used rule of thumb to estimate the maximum heart rate a person can achieve during exercise. It is used to determine target heart rate zones for aerobic training, typically 50‑85% of HRmax. While convenient, it has significant individual variability and is less accurate for older adults and athletes. Alternative formulas (e.g., Tanaka: 208 – 0.7×age) are also used. It is used in fitness testing, rehabilitation, and sports performance. Understanding this estimate helps individuals exercise safely and effectively, though it should be complemented with perceived exertion and actual performance.
Worked example
Estimated Maximum Heart Rate – Two Detailed Examples
Real‑World| Parameter | Value |
|---|---|
| age (yr) | 40 |
| Parameter | Value |
|---|---|
| age | 25 |
Common mistakes
- HRmax: Maximum heart rate – estimated as 220 − age.
- Age in years: Use chronological age.
- Variability: The formula is a population average – actual max heart rate can vary by ±10‑15 bpm.
- Alternative formulas: 207 − 0.7×age (for fitter individuals) – may be more accurate.
- Exercise stress test: For precise HRmax, do a stress test rather than rely on formulas.
Applications
The estimated maximum heart rate (HRmax = 220 − age) is a simple rule of thumb used to guide exercise intensity and to set target heart rates. It is widely used in fitness and clinical settings, though it has variability among individuals. Exercise physiologists and fitness trainers use it to prescribe safe and effective workout intensities, typically aiming for 50‑85% of HRmax. By using HRmax, individuals can monitor their effort, ensuring they are training in the correct zone for cardiovascular fitness, fat burning, or anaerobic conditioning. While more accurate formulas exist, this simple estimate remains popular due to its ease of use. Understanding HRmax is a cornerstone of cardiovascular exercise prescription.
- Exercise prescription and intensity monitoring in fitness programmes
- Cardiac rehabilitation and clinical exercise testing
- Sports performance training (zone training)
- Personal training and group fitness instruction
- Health risk assessment and safety during exercise
Related calculators · Physiological Systems
Recently updated formulas
Suggest an improvement
Found a mistake? Have a better example? Let us know.
You may send up to 3 suggestions per 24 hours.