Home
Back
Heart Rate Calculation Formula:
| From: | To: |
Heart rate calculation from ECG tracing is a method to determine the number of heartbeats per minute by measuring the distance between QRS complexes on an electrocardiogram. The "large boxes" method is one of the simplest and most commonly used techniques in clinical practice.
The calculator uses the following formula:
Where:
Explanation: Standard ECG paper moves at 25 mm/s, with each large box representing 0.2 seconds. There are 300 large boxes in one minute (60 seconds ÷ 0.2 seconds per box = 300 boxes).
Details: Accurate heart rate measurement is essential for diagnosing various cardiac conditions, monitoring patient status during procedures, assessing response to treatment, and determining appropriate medication dosages.
Tips: Count the number of large boxes between two consecutive R waves on the ECG tracing. Enter this value in the calculator. The value must be greater than zero.
Q1: What if the rhythm is irregular?
A: For irregular rhythms, calculate the rate over several beats and take an average, or use the 6-second method (count beats in 6 seconds and multiply by 10).
Q2: How accurate is the large box method?
A: It provides a quick estimate but may be less precise for very fast or very slow heart rates. For precise measurement, digital calipers or automated ECG analysis are preferred.
Q3: What is a normal heart rate range?
A: For adults, normal resting heart rate is typically 60-100 bpm. Athletes may have lower resting rates (40-60 bpm).
Q4: Can this method be used for pediatric patients?
A: Yes, the method works the same way, though normal heart rate ranges differ significantly by age in pediatric patients.
Q5: What are the limitations of this method?
A: It assumes regular rhythm and standard paper speed (25 mm/s). It may be difficult to use with very fast (>150 bpm) or very slow (<50 bpm) heart rates.