Heart Rate Zone & Zone 2 Calculator

What Heart Rate Zones Actually Mean

Heart rate zones are just a structured way to talk about how hard your heart is working. Instead of “easy” or “hard,” we anchor your training to percentages of your estimated maximum heart rate and organize them into Zones 1–5.

This helps you match your cardio intensity to your training goal: long, easy Zone 2 work for health and endurance, or shorter bursts in Zones 4–5 if you’re chasing speed and power.

How This Calculator Estimates Your Max Heart Rate

There’s no perfect formula for max heart rate, but some models are more realistic than others. This calculator uses:

• Tanaka formula: 208 − 0.7 × age (primary estimate)
• Classic formula: 220 − age (reference only)

For most people, Tanaka tends to be a bit more accurate, especially if the classic “220 − age” overshoots your real-world max. If you’ve done a lab test or hard field test, you can mentally compare those numbers to the output here.

Zone 2: The Most Underrated Training Zone

Zone 2 usually feels “too easy” — you can talk in full sentences, breathing is under control, and you finish sessions feeling more energized than destroyed. That’s exactly the point.

Consistent Zone 2 work helps you:

• Build a deeper aerobic base so all other training feels easier
• Improve how efficiently you use fat for fuel
• Support long-term heart and metabolic health
• Recover better between hard strength or sprint sessions

How Much Zone 2 Should You Do?

Most evidence and guidelines for cardio suggest at least 90–150 minutes per week of moderate-intensity work. In practice, that could look like:

• 3 × 30–40 minutes of Zone 2
• 4–5 × 20–30 minutes, if you prefer shorter sessions
• A mix of longer weekend work and shorter weekday sessions

If you’re already training hard with weights or HIIT, start at the low end of that range. If you’re newer, recovering from a layoff, or focused heavily on endurance sports, nudging toward the higher end is often appropriate.

Using Zones With Your Other PhysiqueFormulas Tools

Heart rate zones are only half the equation. To actually change your physique, you still need:

• A calorie target that matches your fat-loss or muscle-gain goal (use the TDEE Calculator)
• Protein and macro targets that support recovery (use the Protein and Macro calculators)
• Strength training 2–4× per week to preserve or build lean mass

Combine the zone data from this page with your nutrition numbers and training plan, and you have a complete, realistic framework instead of random workouts.