Heart rate zones: calculate your zone 2 and training intensities
Calculate your 5 heart rate zones from your age and resting heart rate, using the Tanaka formula or Karvonen method.
Short answer
Your maximum heart rate can be estimated using 208 − 0.7 × age, giving 187 bpm at age 30. Zone 2, easy endurance, is around 60 to 70% of your heart rate reserve: a pace where you can still talk. A maximum heart rate measured during a test remains more reliable than any formula.
Calculator
Validated inputsYour settings
Maximum HR
--
bpm • Tanaka formula
HR Reserve
--
bpm • max HR - resting HR
Zone 2
--
bpm • 60-70% HR reserve
Your 5 training zones
Cardiac profile
How to use it
💡 The Zone 2 corresponds to easy endurance: you can still hold a conversation.
💡 To measure your resting HR, take it on waking before getting out of bed, for 3 consecutive days, and calculate the average.
💡 The Karvonen method takes your resting heart rate into account. If you know your max heart rate measured during a test, it is still more reliable than any formula.
What the tool measures
Useful zones, as long as you don't treat them as gospel
Heart rate zones divide exercise into intensities, from recovery to sprinting. They rely on an estimate of your maximum heart rate. The classic 220 − age formula is often off the mark; Tanaka's formula, 208 − 0.7 × age, derived from a meta-analysis of 351 studies, is more accurate on average. Individual error remains around 10 beats per minute.
Zone 2 has become trendy. It is simply easy endurance exercise, at a pace where you can talk. Endurance athletes do about 80% of their training volume at low intensity. For most people, moving regularly still matters most, whatever the zone.
Interpreting the result
Interpret without overpromising
- Zone 1: recovery, brisk walking.
- Zone 2: easy endurance, conversation possible.
- Zone 3: tempo, conversation becomes difficult.
- Zone 4: threshold, just a few words.
- Zone 5: maximum effort, a few dozen seconds to a few minutes.
The talk test is a good cross-check: if your watch says zone 2 but you can no longer talk, trust your breathing.
Calculation and assumptions
Methodology
- Max HR = 208 − 0.7 × age (Tanaka, 2001).
- Tanaka method: each zone = percentage of max HR (50-60, 60-70, 70-80, 80-90, 90-100%).
- Karvonen method: target HR = resting HR + percentage × (max HR − resting HR), with the same percentages applied to heart rate reserve.
The division into 5 zones is a training convention, not a physiological boundary. Your actual thresholds are measured in a laboratory.
Sources consulted
Sources
- Tanaka et al. (2001) : Age-predicted maximal heart rate revisited
Meta-analysis and laboratory study: max HR = 208 − 0.7 × age, more accurate than 220 − age in adults.
- Karvonen et al. (1957) : The effects of training on heart rate, a longitudinal study
Original paper on the heart rate reserve method.
- Seiler (2010) : What is best practice for training intensity and duration distribution in endurance athletes?
Review of training intensity distribution in endurance athletes: around 80% of volume at low intensity.
Scope of validity
Limitations to know
- Estimated max HR can differ from your actual value by around 10 bpm, sometimes more.
- Beta-blockers and certain other medicines alter heart rate: the calculated zones do not apply.
- Before returning to intense exercise after a long break, or if you have heart disease or symptoms during exercise (chest pain, feeling unwell, unusual breathlessness), consult a doctor.
Frequently asked questions
Before using the result
How do you calculate your maximum heart rate?
The Tanaka formula, 208 − 0.7 × age, is more accurate than 220 − age. It gives 187 bpm at age 30 and 173 bpm at age 50. It can differ from your actual value by around ten beats.
What is zone 2?
An easy endurance intensity, around 60–70% of your heart rate reserve, where you can still hold a conversation. It lets you build training volume without too much fatigue.
How much time in zone 2 per week?
General health guidelines aim for 150 to 300 minutes of moderate activity per week. You can do a good share of this in zone 2, with some higher-intensity exercise alongside it.
Do you need a heart rate chest strap?
It's more accurate than a wrist sensor, especially during changes in intensity. For easy endurance exercise, the talk test is often enough.