Uses your resting heart rate for more personalized zones.
Heart Rate Zones Visualization
Understanding Heart Rate Zones
Zone 1 - Recovery
Very light effort, warm-up/cool-down
50-60% of max HR (130-142 bpm)
Zone 2 - Fat Burn
Light effort, improves fat oxidation
60-70% of max HR (142-154 bpm)
Zone 3 - Aerobic
Moderate effort, builds endurance
70-80% of max HR (154-166 bpm)
Zone 4 - Threshold
Hard effort, improves performance
80-90% of max HR (166-178 bpm)
Zone 5 - Maximum
Maximum effort, very short bursts
90-100% of max HR (178-190 bpm)
Training Benefits by Zone
| Zone | Primary Benefit | Recommended Duration | Feeling |
|---|---|---|---|
| Zone 1 | Recovery, warm-up | 5-30 min | Very easy, can talk normally |
| Zone 2 | Fat burning, base fitness | 30-90 min | Comfortable, can hold conversation |
| Zone 3 | Aerobic endurance | 20-60 min | Moderate, can speak in sentences |
| Zone 4 | Lactate threshold, speed | 10-30 min | Hard, can only say few words |
| Zone 5 | Max performance, VO2 max | 1-5 min intervals | Maximum, cannot talk |
Heart Rate Formulas
Standard Method
Max HR = 220 - Age
Target HR = Max HR x % Intensity
Example: Age 30, Zone 3 (70-80%)
Max HR = 220 - 30 = 190
Target = 133-152 bpm
Karvonen Method
HRR = Max HR - Resting HR
Target = (HRR x %) + Resting HR
Example: Age 30, RHR 70, Zone 3
HRR = 190 - 70 = 120
Target = 154-166 bpm
Explore Heart Rate Scenarios
Explore how changes affect your results
Your Resting Heart Rate vs Population
Compared to the general population
Your Resting HR
70 bpm
Percentile
45th
You're in the ideal range!
Distribution
Excellent
55
Good
62
Average
72
Below Avg
80
Poor
90
Population Average
72
Ideal Range
55 - 70
bpm
Your Ranking
Top 45%
55% are higher
Heart Rate Training Tips
Based on your results
Your Target Zone
Zone 3 (154-166 bpm) is ideal for building aerobic endurance. Monitor your heart rate during exercise to stay in this range.
Maintain Fitness
Your resting HR of 70 bpm shows good cardiovascular fitness. Continue regular training to maintain or improve.
Training Distribution
The 80/20 rule: Spend 80% of training time in Zones 1-2 (easy) and 20% in Zones 4-5 (hard). This maximizes adaptation while preventing burnout.
Frequently Asked Questions
What is target heart rate?
Target heart rate (THR) is the heart rate range that provides optimal cardiovascular benefits during exercise. It's typically expressed as a percentage of your maximum heart rate. Training in your target zone ensures you're working hard enough to improve fitness without overexerting yourself.
How do I calculate my maximum heart rate?
The most common formula is 220 minus your age. For a 30-year-old, max HR = 220 - 30 = 190 bpm. More accurate formulas exist (like Tanaka: 208 - 0.7 × age) but 220 - age is widely used for its simplicity. The only truly accurate way is a clinical stress test.
What is the Karvonen formula?
The Karvonen formula (Heart Rate Reserve method) accounts for your resting heart rate: THR = ((MHR - RHR) × %Intensity) + RHR. This is more personalized than the standard method because it considers your fitness level through resting heart rate. Athletes with lower resting HR will get different zones.
What are heart rate training zones?
Heart rate zones divide exercise intensity into 5 levels: Zone 1 (50-60%) for recovery, Zone 2 (60-70%) for fat burning, Zone 3 (70-80%) for aerobic endurance, Zone 4 (80-90%) for anaerobic threshold, and Zone 5 (90-100%) for maximum performance. Each zone provides different physiological benefits.
Which zone burns the most fat?
Zone 2 (60-70% max HR) is called the "fat burning zone" because the highest percentage of calories burned comes from fat. However, higher intensity zones burn more total calories overall. For weight loss, total calorie burn matters more than the fat percentage.
How do I measure my resting heart rate?
Measure your heart rate first thing in the morning before getting out of bed. Count your pulse for 60 seconds or for 15 seconds and multiply by 4. Average several days for accuracy. A fitness tracker worn overnight can also provide accurate readings.
How this works
Formulas are implementations of published clinical or public-health equations. Calculations run in your browser — no inputs are transmitted to our servers and no account is required. The result is informational; it does not diagnose, treat, or replace advice from a clinician.
What this tool can’t do
When to consult a professional
Talk to a licensed healthcare provider before using the output of this tool to make a medical decision, especially if you have an underlying condition, are pregnant, or are on medication that affects metabolism or fluid balance.
Sources
- [1]Centers for Disease Control and Prevention (CDC)Official sourcecdc.govAccessed Apr 21, 2026
- [2]National Institutes of Health (NIH)Official sourcenih.govAccessed Apr 21, 2026
Full-stack software engineer specializing in embedded systems, web architecture, and AI/ML. Founder of Practical Web Tools. Built the gesture-controlled drone IP acquired by KD Interactive (Aura Drone, sold on Amazon).