Atrial Fibrillation (AFib) Heart Rate Calculator
Calculate your ventricular rate accurately during irregular rhythms.
How to Calculate Heart Rate in Atrial Fibrillation
Calculating heart rate in Atrial Fibrillation (AFib) is significantly different from measuring a regular heart rhythm. Because AFib is "irregularly irregular," the time between individual beats changes constantly. Using a standard 10-second pulse check can lead to highly inaccurate readings.
The most accurate way to measure heart rate in AFib is to count the pulses for a full 60 seconds. If that is not possible, clinical guidelines suggest using at least a 15-second or 30-second window to minimize the margin of error caused by the varying intervals between beats.
The Formula for AFib Ventricular Rate
The calculation uses the following mathematical logic:
Example Calculations
Example 1 (6-Second Rule): If you are looking at a 6-second EKG strip and count 9 R-waves, your heart rate is 90 BPM (9 × 10).
Example 2 (30-Second Manual Count): If you count your pulse for 30 seconds and feel 55 beats, your calculation would be 55 × 2 = 110 BPM. This indicates tachycardia (rapid heart rate).
Interpreting Your AFib Heart Rate
- Controlled AFib: Usually between 60 and 100 BPM at rest.
- AFib with RVR (Rapid Ventricular Response): Resting heart rate consistently above 100 BPM. This often requires medical intervention.
- Bradycardia in AFib: A heart rate below 60 BPM, which may occur due to medications or underlying conduction issues.
Best Practices for Accuracy
- Use a full minute: Especially if your pulse feels very erratic.
- Stay Still: Sit quietly for at least 5 minutes before taking your measurement.
- Check multiple times: Take three readings and average them to get the most reliable data for your healthcare provider.
Note: This calculator is for educational purposes. If you are experiencing chest pain, severe shortness of breath, or dizziness, seek immediate medical attention regardless of your calculated heart rate.