Target Heart Rate Calculator
Calculate your optimal target heart rate range for fat burning, aerobic endurance, tempo runs, and peak VO2 max workouts.
Calculate Target Heart Rate Range (HR_target = HR_rest + % × HRR)
Enter your age, resting heart rate, and desired intensity to calculate your target workout heart rate.
Calculation Results
Calculated using verified physical methodology: \text{HR}_{\text{target}} = \text{HR}_{\text{rest}} + \% \times (\text{HR}_{\text{max}} - \text{HR}_{\text{rest}}) \quad \text{(Karvonen Method)}
Quick Summary
The Target Heart Rate Calculator evaluates target cardiovascular heart rate ranges ($\text{HR}_{\text{target}} = \text{HR}_{\text{rest}} + \% \times \text{HRR}$) for specific training zones including fat burn, aerobic base, tempo, threshold, and maximum interval efforts.
Formula Explanation
\text{Max Heart Rate: } \text{HR}_{\text{max}} = 220 - \text{Age}
\text{Heart Rate Reserve: } \text{HRR} = \text{HR}_{\text{max}} - \text{HR}_{\text{rest}}
\text{Target Range: } \text{HR}_{\text{target}} = \text{HR}_{\text{rest}} + (\text{Intensity\%} \times \text{HRR})How It Works
The Target Heart Rate Calculator computes your maximum heart rate using the standard age formula ($\text{HR}_{\text{max}} = 220 - \text{Age}$). When resting heart rate is provided, it applies the Karvonen formula to calculate Heart Rate Reserve ($\text{HRR} = \text{HR}_{\text{max}} - \text{HR}_{\text{rest}}$) and outputs precise heart rate bounds for the selected intensity zone.
Step-by-Step Worked Example
Practical Problem: A 30-year-old athlete with a resting heart rate of 60 bpm wants to target an Aerobic Base workout (60% to 70% intensity). Calculate target heart rate range.
- Step 1: Max HR: $\text{HR}_{\text{max}} = 220 - 30 = 190\text{ bpm}$.
- Step 2: Heart Rate Reserve (HRR): $\text{HRR} = 190 - 60 = 130\text{ bpm}$.
- Step 3: Lower bound (60%): $60 + (0.60 \times 130) = 60 + 78 = \mathbf{138\text{ bpm}}$.
- Step 4: Upper bound (70%): $60 + (0.70 \times 130) = 60 + 91 = \mathbf{151\text{ bpm}}$.
- Step 5: Target range: Maintain heart rate between 138 bpm and 151 bpm during workout.
Real-World Calculation Examples
Scenario 1: 25-Year-Old Fat Burn Workout
Parameters: Age 25, Rest HR 60 bpm, Fat Burn Zone (50–60%)
Result: 128 – 141 bpm. Ideal intensity for long, easy fat-burning runs.
Scenario 2: 35-Year-Old Tempo Run
Parameters: Age 35, Rest HR 55 bpm, Tempo Zone (70–80%)
Result: 146 – 159 bpm. Sustainable hard effort for 10K/Half Marathon pacing.
Scenario 3: 45-Year-Old Threshold Interval
Parameters: Age 45, Rest HR 65 bpm, Threshold Zone (80–90%)
Result: 153 – 164 bpm. Anaerobic threshold training bounds.
Scenario 4: 55-Year-Old Walking Recovery
Parameters: Age 55, Rest HR 70 bpm, Recovery Zone (50–60%)
Result: 118 – 127 bpm. Active recovery walking target.
Key Benefits of Using This Calculator
Karvonen Precision Method
Incorporates individual resting heart rate to calculate Heart Rate Reserve (HRR) for personalized bounds.
5 Workout Intensity Zones
Covers all major training intensities: Fat Burn, Aerobic Base, Tempo, Threshold, and VO2 Max Peak.
Instant Real-Time Calculation
Updates instantly as age, resting heart rate, or target intensity selections change.
100% Free & Client-Side
Executes locally in your browser with zero latency or web server transmission.
Frequently Asked Questions (FAQ)
What is target heart rate?
Target heart rate is the range of heart beats per minute (bpm) desired during physical exercise to enable specific cardiovascular and metabolic adaptations.
How is maximum heart rate calculated?
The most common formula is $\text{HR}_{\text{max}} = 220 - \text{Age}$. Tanaka's formula ($\text{HR}_{\text{max}} = 208 - 0.7 \times \text{Age}$) is also widely used for adults over 40.
Why is resting heart rate important for target HR?
Resting heart rate reflects cardiovascular efficiency. Using resting HR with the Karvonen formula prevents overestimating intensity for fit individuals with low resting HRs.
What heart rate zone burns the most fat?
Zone 1/2 (50% to 70% of HRR) uses fat as the primary fuel source per minute, though higher intensities burn more total calories overall.
What is a good target heart rate for a 30-year-old?
For general aerobic endurance (Zone 2), a 30-year-old typically targets 114–133 bpm (standard method) or 138–151 bpm (Karvonen with 60 bpm rest HR).
How long should I stay in my target heart rate zone?
The American Heart Association recommends at least 30 minutes per day, 5 days per week in Zone 2/3 for optimal cardiovascular health.
What happens if my heart rate goes above my target zone?
Exceeding target zone shifts energy metabolism from aerobic to anaerobic, causing rapid lactate accumulation and early muscular fatigue.
Can medication affect target heart rate?
Yes — medications such as beta-blockers lower both resting and peak heart rate. Individuals on heart medication should consult their doctor for personalized targets.
How accurately do smartwatches measure target heart rate?
Optical wrist sensors are generally accurate within 3–5 bpm during steady-state exercise, but chest strap monitors remain the gold standard for interval training.
Is it normal for target heart rate to fluctuate during a workout?
Yes — heart rate drift naturally causes HR to rise gradually during prolonged exercise even at constant pace, due to body temperature rise and fluid loss.