The Corrected QT Interval (QTc) calculator is an essential tool in evaluating heart health by analyzing the heart's electrical activity. This is done using inputs such as the QT interval (in milliseconds), heart rate (in beats per minute), and a formula choice to compute the QTc value.

To begin, the calculator determines the RR interval, which is the period between heartbeats, by using the formula RR = 60 / heartRate. This step accounts for variations in heart rate when calculating the QTc.

Depending on the formula selected by the user, the adapted QTc is computed through different methods:

- Bazett's Formula: QTc is derived by dividing the QT interval by the square root of the RR interval.
- Fridericia's Formula: QTc involves dividing the QT interval by the cube root of the RR interval.
- Framingham's Formula: QTc is calculated by adding the QT interval to 154 multiplied by (1 - RR).
- Hodges' Formula: QTc adds the QT interval to 1.75 times the difference between heart rate and 60.

After calculating the QTc, the result is rounded to the closest integer. The interpretation of this QTc value is categorized into specific ranges to assess its clinical significance, as follows:

- Short QTc: Below 350 ms, which may indicate abnormally rapid heart repolarization.
- Normal QTc: From 350 to 430 ms, considered typical and healthy.
- Borderline QTc: Between 431 and 450 ms, slightly outside the optimal range.
- Prolonged QTc: From 451 to 500 ms, which can suggest a potential risk for arrhythmias.
- Severely Prolonged QTc: Over 500 ms, indicating a significantly elevated risk for heart-related events.

Understanding whether a QTc falls into the normal or one of the abnormal categories can help in diagnosing conditions involving heart rhythm irregularities.

The Corrected QT Interval (QTc) Calculator is a tool used to adjust the QT interval (a measure of ventricular depolarization and repolarization on an ECG) for heart rate. The QT interval varies with heart rate, and correcting it provides a standardized measurement to assess the risk of arrhythmias like Torsades de Pointes. This is crucial in clinical settings, especially when monitoring patients on medications that may prolong the QT interval.