🩺 Health calculator

Target Heart Rate Calculator

Find your maximum heart rate and all five training zones — from easy warm-up to all-out VO2 max effort. Know exactly what BPM range to target for fat burning, cardio fitness, or peak performance, and understand what each zone actually does for your body.

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Your maximum heart rate is the foundation of all training zones. Age is the primary input — optionally enter your resting heart rate for more precise zones using the Karvonen method.

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Used to estimate max heart rate
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Measure first thing in the morning

Which formula to use?

Standard (220 − age) is the most common. Tanaka is slightly more accurate for older adults. Gulati was validated specifically for women. Custom lets you use a max HR from a lab test or fitness test.

Resting heart rate (RHR)

Adding your RHR enables the Karvonen method — which calculates zones from your Heart Rate Reserve (HRR = max HR − resting HR). This gives more personalised zones than the % of max HR method alone.

Tip: measure your resting heart rate lying down for 5 minutes first thing in the morning, before getting up. For most adults it falls between 50–70 BPM. A lower resting HR generally indicates better cardiovascular fitness.
Heart rate zones are general guidelines for healthy adults. Consult a doctor before starting a new exercise programme, especially if you have a heart condition, hypertension, or have been inactive for an extended period.

What is target heart rate?

Target heart rate is the BPM range you aim to maintain during exercise to achieve a specific training effect — fat burning, aerobic fitness, or peak performance. Training at the right intensity ensures you get the outcome you're working toward without under-training or overtraining.

Target heart rate zones are expressed as percentages of your maximum heart rate (MHR). Your MHR is the highest number of times your heart can beat per minute — it declines with age, which is why age is the primary input in most formulas.

Max heart rate formulas

Standard (Fox, 1971): MHR = 220 − age
Tanaka (2001): MHR = 208 − (0.7 × age) — more accurate for adults over 40
Gulati (2010): MHR = 206 − (0.88 × age) — validated specifically for women

The standard formula (220 − age) has a standard deviation of ±10–12 BPM — meaning your actual max HR could realistically be 10–12 BPM higher or lower than the estimate. The only way to know your true MHR is a supervised maximal exercise test.

The 5 heart rate training zones

Zone 1 — Warm-up (50–60% MHR): Very light effort. Recovery, warm-up, cool-down. Can hold a full conversation. Burns mostly fat but at low total calorie rate.
Zone 2 — Fat burn (60–70% MHR): Light-moderate effort. The primary fat-burning zone. Sustainable for long durations. Builds aerobic base. The foundation of endurance training.
Zone 3 — Cardio (70–80% MHR): Moderate-hard effort. Improves aerobic capacity and cardiovascular efficiency. Breathing is heavier, conversation becomes difficult. Good for tempo runs and steady rides.
Zone 4 — Hard (80–90% MHR): Hard effort. Improves speed, lactate threshold, and VO2 max. Can be sustained for 10–20 minutes. Used in interval training and race-pace efforts.
Zone 5 — Maximum / VO2 max (90–100% MHR): Maximum effort. Can only be sustained for seconds to a few minutes. Used in sprint intervals and competitive racing. Not suitable for beginners.

Karvonen method — Heart Rate Reserve

The Karvonen method calculates zones from your Heart Rate Reserve (HRR) rather than raw max HR. HRR = Max HR − Resting HR. Because it accounts for your fitness baseline (resting HR), it gives more personalised zones.

HRR = Max HR − Resting HR
Target HR = (HRR × zone %) + Resting HR
Example: Max HR = 190, RHR = 60, Zone 2 = 60–70%
Lower: (190 − 60) × 0.60 + 60 = 78 + 60 = 138 BPM
Upper: (190 − 60) × 0.70 + 60 = 91 + 60 = 151 BPM

Compare this to the raw % method: 60–70% of 190 = 114–133 BPM. The Karvonen result (138–151) is higher because a resting HR of 60 means your heart has 130 BPM of reserve above resting — and zone training should be set relative to that reserve, not from zero.

Which zone should you train in?

For fat loss: Zone 2 (60–70%) for long sessions. More total calories burned over time than short high-intensity sessions for most people.
For cardiovascular fitness: Mix of Zone 2 (base building) and Zone 4 (threshold intervals). The 80/20 rule — 80% easy, 20% hard — is well-supported by endurance research.
For weight loss efficiency: Zone 3–4 burns more calories per minute but is harder to sustain. Zone 2 burns fewer calories per minute but can be maintained for hours.
For beginners: Start in Zone 1–2. Building an aerobic base first makes higher-intensity training safer and more effective later.
For athletes: Zone 5 intervals (sprints, VO2 max work) improve peak performance but require adequate Zone 1–2 volume to recover between sessions.

Frequently asked questions

How do I find my target heart rate for fat burning?

The fat-burning zone is 60–70% of your maximum heart rate. For a 30-year-old with a max HR of 190, that is 114–133 BPM (or 138–151 BPM using the Karvonen method with a resting HR of 60). This intensity feels comfortable — you can speak in short sentences but not hold a full easy conversation.

What is a good resting heart rate?

For adults, a normal resting heart rate is 60–100 BPM. Athletes often have resting HRs of 40–60 BPM due to cardiac efficiency from training. A consistently elevated resting HR (above 90–100) without explanation is worth discussing with a doctor.

Is the 220 minus age formula accurate?

The 220 − age formula is a rough population average with a standard deviation of ±10–12 BPM. It is a useful starting point but your actual max HR may be meaningfully higher or lower. The Tanaka formula (208 − 0.7 × age) tends to be more accurate for adults over 40.

What happens if I always train in Zone 3?

Zone 3 ("no man's land") is too hard to recover from easily and not hard enough to produce peak adaptations. Research on endurance athletes shows that spending too much time in Zone 3 leads to accumulated fatigue without proportional fitness gains. Most coaches recommend minimising Zone 3 and splitting training between Zones 1–2 and Zones 4–5.

Can I use my smartwatch heart rate for zone training?

Yes, with some caveats. Wrist-based optical heart rate monitors are reasonably accurate at steady-state intensities but can lag or misread during rapid HR changes (sprints, intervals). For high-intensity training, a chest strap monitor gives more reliable real-time readings.

Related health calculators

These tools pair naturally with heart rate zone training.

BMR Calculator Find your base calorie burn — combined with your training zones to plan total daily calorie expenditure. Calorie Deficit Calculator Set a daily calorie target to lose fat at a sustainable pace alongside your cardio training. Body Fat % Calculator Track your body composition progress as your Zone 2 training builds aerobic fitness over time. Lean Body Mass Calculator Estimate your lean mass — useful for setting protein targets to preserve muscle during cardio training.

Disclaimer

This target heart rate calculator provides estimates based on population-level formulas. Individual max heart rate varies significantly from formula predictions. These zones are general guidelines for healthy adults and are not a substitute for professional exercise prescription. Consult a doctor before starting a new exercise programme, particularly if you have cardiovascular disease, hypertension, or have been inactive for an extended period.