Target Heart Rate Zones
Train smarter, not harder. Calculate your 5 heart rate zones to optimize fat burning, build endurance, and improve athletic performance using the Karvonen method.
Max Heart Rate
Your safe upper limit
Fat Burn Zone
Optimize weight loss
Cardio Zone
Build stamina
Peak Zone
High intensity intervals
Why Train in Zones?
Not all cardio is created equal. Your body uses different fuel sources (fat vs. carbs) depending on how fast your heart is beating.
The 5 Heart Rate Zones
Training zones are calculated percentages of your Maximum Heart Rate (MHR). By staying within specific zones, you can target specific fitness goals like recovery, fat loss, aerobic conditioning, or anaerobic power.
Zone 1: Warm Up (50-60%)
Very light effort. Helps with recovery and blood flow.
Zone 2: Fat Burn (60-70%)
Comfortable pace. Body primarily uses fat for fuel. "Conversational pace".
Zone 3: Aerobic (70-80%)
Moderate effort. Improves cardiovascular endurance and lung capacity.
Zone 4: Anaerobic (80-90%)
Hard effort. Improves speed and lactate threshold. Breathing is heavy.
Zone 5: Maximum (90-100%)
All-out effort. Sustainable for very short periods (sprinting). Develops speed.
Karvonen Formula
Uses your Resting Heart Rate (RHR) for a much more personalized result than the standard "220 minus age" formula.
Targeted Results
Get specific BPM (Beats Per Minute) ranges for every training zone instantly.
Adjustable
Easily update your age and resting heart rate as your fitness improves to keep your zones accurate.
Why Use Our HR Calculator?
Avoid Overtraining
Many people train too hard on "easy" days. Knowing your Zone 2 limit prevents burnout.
Maximize Fat Loss
Training in the correct "Fat Burn" zone ensures your body utilizes fat stores rather than just burning glucose.
Simple & Free
No need for expensive smartwatches. Just check your pulse and use this tool.
How to Use the HR Zone Calculator
Get accurate zones in 3 simple steps.
Enter Your Age
Your Maximum Heart Rate (MHR) declines naturally with age. Entering your age allows us to estimate your specific ceiling.
Find Resting Heart Rate
Check your pulse first thing in the morning before getting out of bed. This "Resting Heart Rate" (RHR) is a key indicator of your fitness level and is used in the Karvonen formula.
Get Your Zones
Click calculate. We will provide a detailed chart of your 5 training zones, so you know exactly what heart rate to aim for during your next workout.
Calculate Your Training Zones
Enter your vitals below.
Detailed Zone Guide
What each zone feels like and what it does for your body.
Zone 1: Recovery
Very light intensity. Used for warm-ups or active recovery days. Helps flush out lactic acid.
Zone 2: Endurance
"All day" pace. Essential for building a strong aerobic base. Teaches body to burn fat efficiently.
Zone 3: Aerobic
"Grey Zone". Harder than easy, easier than hard. Improves blood circulation and skeletal muscles.
Zone 4: Threshold
"Uncomfortably hard". You start to feel the burn. Increases lactate threshold and performance speed.
Zone 5: VO2 Max
Maximum effort. Can only be held for minutes. Trains fast-twitch fibers and neuromuscular system.
The Math Explained
Why we use the Karvonen method.
Standard Max HR
220 - Age
Simple but ignores fitness level.
Karvonen Formula (Ours)
Target = ((Max HR − Resting HR) × %Intensity) + Resting HR
More accurate because it factors in your Resting Heart Rate (RHR).
Applications of Zone Training
Who benefits from this calculator?
Runners & Cyclists
80/20 training (80% easy, 20% hard) is the secret to endurance. Use this calculator to find your Zone 2 ceiling so you keep your easy days truly easy.
Fat Loss
Zone 2 is often called the "Fat Burning Zone" because at this lower intensity, the body prefers oxidizing fat for fuel over glycogen (carbs).
Sample Workouts
Not sure how to apply your new numbers? Try these specific workouts for different goals.
The "Base" Builder
Focus: Fat Oxidation & Endurance
Tempo Run
Focus: Anaerobic Threshold
HIIT Intervals
Focus: Speed & Power
How to Check Your Pulse Manually
You don't need expensive technology to train effectively. You can check your heart rate instantly using just your fingers and a clock.
Find your pulse
Place your index and middle finger on your wrist (below the thumb) or on the side of your neck.
Count for 10 Seconds
Using a stopwatch or wall clock, count the number of beats you feel in exactly 10 seconds.
Do the Math
Multiply that number by 6 to get your Beats Per Minute (BPM).
Pro Tip for Accuracy
Measuring Resting HR
Measure it immediately after waking up, before you sit up in bed. Do this for 3 days and take the average.
Measuring Active HR
If you stop running to measure, your heart rate drops rapidly. Count for only 6 seconds and multiply by 10 for a faster reading.
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Frequently Asked Questions
How do I measure Resting Heart Rate?
Best measured right after waking up, while still in bed. Count pulse for 60 seconds, or use a smartwatch.
Is the 220-age formula accurate?
It's a general estimate. It can be off by 10-20 beats. The Karvonen formula used here is better because it accounts for your fitness level via Resting Heart Rate.
Which zone burns the most fat?
Zone 2 burns the highest *percentage* of fat calories. However, higher intensity zones burn more total calories in less time, but mix fuel sources.
Why is my Zone 2 so slow?
This is common! Most people naturally run/train in Zone 3 ("Grey Zone"). Training in true Zone 2 feels incredibly slow at first but builds a massive aerobic base over time.