Each large square in the EKG graph paper represents how much time?

In an electrocardiogram (EKG or ECG), each large square on the graph paper corresponds to 0.20 seconds. This is crucial for measuring heart rhythms and intervals accurately. The EKG paper is typically printed at a speed of 25 mm per second, and since each large square measures 5 mm across, it takes 0.20 seconds to traverse one large square.

This measurement is essential for calculating various components of the heart's electrical activity, such as the PR interval, QRS duration, and QT interval, as these can provide critical information regarding cardiac function and potential abnormalities. Understanding this time representation allows clinicians and technicians to assess heart rate and rhythm more efficiently.