Measure an ECG

Drop an image here, paste it (Ctrl+V), or

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Works offline: after your first visit, turn off Wi-Fi and the app still works. An easy way to check that nothing is sent.

1 Image

Straighten 0.0°

Show level guides

Perspective (phone photos)

Drag the orange caliper across a known number of large boxes (1 large box = 5 mm).

Paper speed Gain Horizontal span (boxes) Vertical span (boxes)

Square grid (vertical = horizontal)

March out selected caliper

Drag a leg to adjust it, the bar to move the caliper. Arrow keys nudge by 1 screen pixel (Shift ×10). Delete removes.

Net QRS in I (mm) Net QRS in aVF (mm)

Sectors are fixed textbook ranges applied to the angle, not an interpretation.