Fridericia Formula Calculator

Fridericia Formula Calculator calculator can be used for calculating corrected QT interval (QTc) to account for heart rate variations.

Input Parameters

Calculation Results

Calculation Formula

QTc = QT / (1.08 × (60/HR))

Where:
QTc = Corrected QT interval
QT =QT interval in seconds
HR = Heart rate in beats per minute

Results

Corrected QT (QTc) (seconds): -
Heart Rate: -

Fridericia Formula Calculator Calculator Usage Guide

Learn how to use the Fridericia Formula Calculator calculator and its working principles

What is the Fridericia Formula?

The Fridericia formula is one of several formulas used to correct the QT interval for heart rate variability. It's particularly recommended for Black populations but can be used generally.

How to Use This Calculator

  1. Enter the measured QT interval in seconds (from an ECG reading)
  2. Enter the heart rate in beats per minute (also from an ECG reading)
  3. Click the "Calculate" button to compute the corrected QT interval
  4. The result will be displayed in seconds

Interpreting Results

A prolonged QTc can indicate increased risk of arrhythmias. Reference values vary by population and age group:

  • Adults: typically < 440 ms (or < 0.44 seconds)
  • Children: varies by age (generally proportional to BSA)

Important Notes

The Fridericia formula is preferred over Bazett's formula for Black populations due to lower over-correction. However, it tends to over-correct in individuals with very high heart rates. Always interpret results in clinical context with other ECG findings.