Eye Chart – Web (distance-calibrated, Embeddable)

Eye Chart – Distance‑Calibrated (Web)

Safety: Do not use for diagnosis. For screening/demo only.

Test distance (cm)

Param: d= (cm)

Screen scale calibration

Adjust so rectangle = 85.60 mm × 53.98 mm

Chart type Sloan letters Tumbling E Landolt C

Param: type=sloan|e|c

Smallest line (Snellen) 20/10 20/20 20/25 20/32 20/40 20/50

Largest line (Snellen) 20/50 20/100 20/160 20/200 20/400

Rows

Contrast

Randomize / Static

Fullscreen / Fit

Embed via iframe with params: ?d=300&type=sloan&min=20/20&max=20/100&rows=8&contrast=1&flip=0

TrueDepth note: Native iOS apps can pass real distance via window.postMessage({type:'distanceCM', value}). This page listens for it.