Training by heart rate turns guesswork into a plan. Instead of wondering whether you’re working hard enough, you aim for a specific beats-per-minute range that matches your goal — fat loss, endurance, or speed. This guide explains your maximum heart rate, the five training zones, the famous “fat burning zone,” and the more accurate Karvonen method. For instant numbers, use our free Heart Rate Zone Calculator.

How to Find Your Maximum Heart Rate

Your maximum heart rate (MHR) is the ceiling your heart can reach during all-out effort. Two common estimates:

Basic: Max HR = 220 − age. Tanaka (often more accurate): Max HR = 208 − 0.7 × age.

For a 30-year-old, that’s about 190 bpm. These are estimates — your real max can be 10–20 bpm higher or lower, and only a supervised test gives a precise figure.

The 5 Heart Rate Training Zones

• Zone 1 — Recovery (50–60%): very easy; warm-ups, cool-downs, active recovery.
• Zone 2 — Fat Burn (60–70%): comfortable, conversational; builds endurance and uses fat as fuel.
• Zone 3 — Aerobic (70–80%): moderate; improves overall cardio fitness.
• Zone 4 — Anaerobic (80–90%): hard; develops speed and performance.
• Zone 5 — Peak (90–100%): all-out; short intervals for max power.

The American Heart Association suggests most people train at 50–85% of max HR — roughly Zones 2 to 4 — for general fitness.

The Fat Burning Zone — Truth and Myth

Zone 2 (about 60–70% of max HR) is called the “fat burning zone” because your body uses the highest percentage of fat for fuel there. But the part people miss: higher zones burn more total calories per minute, so they can produce greater overall fat loss even though a smaller share comes directly from fat. The best results usually come from a mix — plenty of easy Zone 2 work to build an aerobic base, plus some higher-intensity intervals. Don’t stress about staying glued to one zone.

The Karvonen Method (More Personalized)

The basic method uses only your max heart rate. The Karvonen method also factors in your resting heart rate, a marker of fitness, for more tailored zones:

Target HR = ((Max HR − Resting HR) × intensity %) + Resting HR

Example: Max 190, resting 60, at 70% intensity → ((190 − 60) × 0.70) + 60 = 151 bpm. Because a fitter person has a lower resting heart rate and a bigger “reserve,” Karvonen is preferred by the American College of Sports Medicine for setting training intensity. Add your resting heart rate to the calculator to use it.

How to Measure Your Resting Heart Rate

Measure first thing in the morning, before getting out of bed. Find your pulse at the wrist or neck, count beats for 30 seconds, and double it. Average a few mornings for a reliable figure. A typical resting heart rate is 60–100 bpm; trained athletes are often below 60. If yours trends downward over weeks of training, that’s a sign your fitness is improving.

How to Use Zones for Your Goal

• Fat loss / general health: mostly Zone 2, with occasional Zone 4 intervals.
• Endurance (5K, 10K, marathon): a large base of Zone 2, some Zone 3–4 tempo work.
• Speed & power: short, hard Zone 4–5 intervals with full recovery.
• Recovery days: keep it in Zone 1 — easy really does mean easy.

A Note on Safety

Heart rate formulas are estimates, and some medications (like beta-blockers) change your heart rate significantly. If you have a heart condition, are pregnant, take heart medication, or have been inactive, check with a doctor before starting or intensifying exercise. Listen to your body — the “talk test” is a useful companion to the numbers: in Zone 2 you can hold a conversation; in Zone 4 you can only manage short phrases.