People type this into search every day: heart rate zone calculator.
A single “fat burning zone” number leaves out the age estimate and the two bands the American Heart Association publishes. The bands are percents of an estimated maximum. They are averages.
This page uses the heart rate training zones calculator. It is a guide built from that AHA method. It is not a diagnosis, a training plan, or medical advice. AHA notes that some drugs and conditions change the useful range. Ask a clinician what target fits a heart condition or a medication before you chase a percent.
220 minus age, then 50, 70, and 85 percent
AHA’s target heart rates chart estimates maximum heart rate as about 220 minus age. Moderate-intensity activity is about 50 to 70 percent of that maximum. Vigorous activity is about 70 to 85 percent. The 50 to 85 percent span is the full target zone on their chart.
The calculator does this:
Estimated maximum = 220 − age, with age kept between 1 and 120
Each band edge = that maximum × the percent, rounded to the nearest whole beat
Moderate runs from the rounded 50% figure up to the rounded 70% figure.
Vigorous runs from the rounded 70% figure up to the rounded 85% figure.
The result line is the rounded 50% figure through the rounded 85% figure.
If you type a pulse above 0, the tool names a band:
- under the rounded 50% line: below the AHA moderate range
- from that line up to, but not including, the rounded 70% line: moderate
- from the rounded 70% line through the rounded 85% line: vigorous
- over the rounded 85% line: above the AHA vigorous range
The 70% beat is the top of the moderate label and the bottom of the vigorous label. A pulse that lands on it is called vigorous, because moderate stops strictly below that beat.
The calculator’s own age-35 example matches the row it attributes to AHA’s chart: a maximum of 185 and a target of 93 to 157. Example 2 is that row, with the rounding written out.
Fig 1
Age to a maximum, then two bands
A typed pulse is compared with the rounded edges
Maximum heart rate is 220 minus age. Moderate is about 50 to 70 percent of that maximum. Vigorous is about 70 to 85 percent. The pulse lands in one of those bands, or outside them.
The one-rep max post estimates a lifting load from a set you already did. The daily calorie calculator estimates energy from size and an activity level.
Example 1: age 20, where the percents land on whole numbers
Age 20. Activity heart rate left at 0, so the result is the zones only.
Maximum: 220 − 20 = 200 bpm
50% of 200 = 100
70% of 200 = 140
85% of 200 = 170
Moderate: 100 to 140 bpm
Vigorous: 140 to 170 bpm
Full target: 100 to 170 bpm
No rounding was required. A pulse of 140 is vigorous, because it sits on the 70% line. A pulse of 139 is moderate. A pulse of 170 is still vigorous. A pulse of 171 is above the vigorous range.
Example 2: age 35, the published row
Age 35. Pulse left at 0.
Maximum: 220 − 35 = 185 bpm
50% of 185 = 92.5, which rounds to 93
70% of 185 = 129.5, which rounds to 130
85% of 185 = 157.25, which rounds to 157
Moderate: 93 to 130 bpm
Vigorous: 130 to 157 bpm
Full target, the result line: 93 to 157 bpm
Calculator result
Heart rate training zones
- Age
- 35 years
- Heart rate during activity
- 0 bpm
93–157 bpm
AHA 50–85% target heart-rate zone
- Estimated maximum heart rate
- 185 bpm
- Moderate intensity (50–70%)
- 93–130 bpm
- Vigorous intensity (70–85%)
- 130–157 bpm
Fig 2 · 1/4
The four slices of a 185 bpm maximum
Age 35. Shares are 50, 20, 15, and 15 percent, before rounding.
Under 50%
below 93
Moderate
93–130
Vigorous
130–157
Above 85%
over 157
Under 50 percent is below 93 bpm.
Moderate is 93 to 130 bpm, about 20 percent of the max.
Vigorous is 130 to 157 bpm.
Above 85 percent is over 157 bpm.
The labels are the rounded beats. The widths are the percent bands AHA describes, which add to 100. Rounding is why 93 is not exactly half of 185.
Example 3: a pulse of 120 at age 35
Same age. Heart rate during activity: 120.
The zones do not move. The result is still 93 to 157 bpm. The extra line is 120 bpm, AHA moderate intensity.
120 is above 93 and below 130, so it stays in moderate. It is 130 − 120 = 10 beats under the vigorous line.
Calculator result
Heart rate training zones
- Heart rate during activity
- 120 bpm
93–157 bpm
AHA 50–85% target heart-rate zone
- Estimated maximum heart rate
- 185 bpm
- Moderate intensity (50–70%)
- 93–130 bpm
- Vigorous intensity (70–85%)
- 130–157 bpm
Example 4: 150, 90, and 160 at the same age
Three pulses, age still 35. The zones stay 93 to 130 moderate and 130 to 157 vigorous.
150 bpm. 150 is between 130 and 157. The line reads 150 bpm, AHA vigorous intensity. It is 157 − 150 = 7 beats under the top of vigorous.
90 bpm. 90 is under 93. The line reads 90 bpm, Below the AHA moderate range. The gap is 3 beats.
160 bpm. 160 is over 157. The line reads 160 bpm, Above the AHA vigorous range. The gap is 3 beats.
A pulse of 0 does not get a band. The field is optional. Leaving it empty, which the default does, only prints the zones.
Example 5: the beat the two labels share
Age 35. The rounded 70% line is 130.
129 bpm is under 130, so the band is AHA moderate intensity.
130 bpm is not under 130. It is inside vigorous, up through 157. The band is AHA vigorous intensity.
93 bpm is the bottom of moderate. The below-moderate label starts under 93.
157 bpm is the top of vigorous. The above-vigorous label starts at 158.
158 bpm is above the vigorous range.
One beat changes the label at 130 and at 158. It does not change the estimated maximum, which is still 185.
Example 6: age 25, 50, and 70
The formula is the same. These are the beats the calculator prints. Where a percent does not land on a whole number, use the printed beat.
Age 25. Maximum 220 − 25 = 195. Moderate 98 to 137. Vigorous 137 to 166. Target 98 to 166.
A pulse of 110 is moderate. 110 sits between 98 and 137.
Age 50. Maximum 220 − 50 = 170. Moderate 85 to 119. Vigorous 119 to 145. Target 85 to 145.
A pulse of 145 is vigorous. It is the top of the range, and the rule includes that beat.
Age 70. Maximum 220 − 70 = 150. Moderate 75 to 105. Vigorous 105 to 128. Target 75 to 128.
A pulse of 75 is moderate. It is the bottom of the range, and the rule includes that beat. A pulse of 128 is vigorous. A pulse of 74 would be below moderate.
Fig 3 · 1/6
Estimated maximum by age
220 minus age, every 10 years
Estimated maximum heart rate
- 220 − age
| Point | 220 − age |
|---|---|
| 20 | 200 |
| 30 | 190 |
| 40 | 180 |
| 50 | 170 |
| 60 | 160 |
| 70 | 150 |
At 20 the estimate is 200 bpm.
At 40 it is 180 bpm.
At 70 it is 150 bpm.
From 20 to 70 the estimate falls by 50 beats, one beat per year of age. That is the whole of the 220 − age formula. It is an average, which is why AHA tells you to treat the chart as a guide.
Example 7: what if the age is 10 or 20 years off
Hold the pulse at 120 and change only the age.
Age 35. Zones from example 2. 120 is below 130, so moderate.
Age 45. Maximum 220 − 45 = 175. Moderate 88 to 122. Vigorous 122 to 149. Target 88 to 149.
120 is still below the vigorous line at 122, so the band is still moderate. The label did not change. The room inside moderate did. At 35, 120 had 10 beats of moderate left above it. At 45, it has 122 − 120 = 2 beats left.
Age 55. Maximum 220 − 55 = 165. Moderate 83 to 115. Vigorous 115 to 140. Target 83 to 140.
120 is no longer under 115. It is inside 115 to 140, so the band is vigorous.
Calculator result
Heart rate training zones
- Age
- 55 years
- Heart rate during activity
- 120 bpm
83–140 bpm
AHA 50–85% target heart-rate zone
- Estimated maximum heart rate
- 165 bpm
- Moderate intensity (50–70%)
- 83–115 bpm
- Vigorous intensity (70–85%)
- 115–140 bpm
The same 120 bpm reading is moderate at 35 and vigorous at 55. The pulse did not rise. The estimated maximum fell by 20 beats, and the 70% line moved from 130 to 115.
A second pulse, 140, shows the top end of the same idea.
- Age 35: 140 is inside 130 to 157, so vigorous.
- Age 45: 140 is inside 122 to 149, so vigorous.
- Age 55: 140 equals the vigorous top, so vigorous.
- Age 65: maximum 155, vigorous 109 to 132. 140 is over 132, so above the AHA vigorous range.
Fig 4 · 1/2
Where the top of each band sits
Rounded 70 percent and 85 percent of 220 minus age
Beats per minute
- Moderate top
- Vigorous top
| Category | Moderate top | Vigorous top |
|---|---|---|
| Age 25 | 137 | 166 |
| Age 35 | 130 | 157 |
| Age 45 | 122 | 149 |
| Age 55 | 115 | 140 |
| Age 65 | 109 | 132 |
The moderate top falls from 137 bpm at age 25 to 109 at age 65.
The vigorous top falls from 166 bpm at age 25 to 132 at age 65.
Example 8: a cleaner age table from the same formula
Every row is 220 minus the age, then the calculator’s rounded 50%, 70%, and 85%.
| Age | Maximum | Moderate, 50–70% | Vigorous, 70–85% | Target, 50–85% |
|---|---|---|---|---|
| 20 | 200 | 100–140 | 140–170 | 100–170 |
| 25 | 195 | 98–137 | 137–166 | 98–166 |
| 30 | 190 | 95–133 | 133–162 | 95–162 |
| 35 | 185 | 93–130 | 130–157 | 93–157 |
| 40 | 180 | 90–126 | 126–153 | 90–153 |
| 45 | 175 | 88–122 | 122–149 | 88–149 |
| 50 | 170 | 85–119 | 119–145 | 85–145 |
| 55 | 165 | 83–115 | 115–140 | 83–140 |
| 60 | 160 | 80–112 | 112–136 | 80–136 |
| 65 | 155 | 78–109 | 109–132 | 78–132 |
| 70 | 150 | 75–105 | 105–128 | 75–128 |
Age 30 is exact on the maximum: 220 − 30 = 190. The printed bands are 95 to 133 and 133 to 162. Age 40 is 180, with 90 to 126 and 126 to 153. Age 60 is 160, with 80 to 112 and 112 to 136. Age 65 is 155, with 78 to 109 and 109 to 132.
A pulse of 100 at age 65 is moderate. 100 sits between 78 and 109.
Example 9: reading a workout against the row
Take age 50 and a run that spent time at 100, 120, and 150 bpm. Use the age-50 row from the table.
100 bpm is between 85 and 119, so moderate.
120 bpm is not under 119. It is inside 119 to 145, so vigorous. One beat above the shared line changes the label, the same rule as example 5.
150 bpm is over 145, so above the AHA vigorous range.
The calculator classifies one pulse at a time. If you want a single label, type the beat you care about. A blend of the easy minutes and the hard ones is a different question.
What the number does not decide
The estimated maximum is 220 minus age for a general adult chart. A measured maximum from a supervised test is a different number, and this calculator does not take one. Typing a younger age to “raise the zones” moves every edge, which example 7 already measured: 120 bpm changed bands between 35 and 55.
Heat, dehydration, caffeine, and a short steep hill move a pulse without moving the formula. The band name is a comparison with the estimate. It is not a verdict on the session.
If a medication lowers your pulse, AHA’s caution is the one to follow: ask what range fits that prescription. The calculator will still subtract your age from 220. That arithmetic does not know about the drug.
Open the heart rate zone calculator with your age, then with a pulse from a session you have already done. Read the band. If the session felt wrong, or you have a heart condition, ask a clinician before you raise the percent.