Snellen Chart

Snellen Chart is an optically precise eye chart app designed for children (6+), parents and general practitioners to measure distance visual acuity. It displays calibrated optotypes and supports predefined test distances (6, 5, 4, 3, 2 meters and 20, 15, 12, 10, 6 feet). Test scenarios include doctor/patient, mirror self-test, Bluetooth keyboard input and arm's-reach self-testing. Two modes are available: Autoplay and Manual. Enable “Record Scores” to save results for multiple subjects and track vision progression over time.

The app reports scores in Decimal, Fraction, LogMAR, MAR and an intuitive Visual Acuity Score (VAS = 100 − 50 × LogMAR) where higher values mean better acuity. In score review, 100 is the reference standard; values >100 indicate no myopia and values <100 may indicate myopia. Snellen Chart helps with early myopia screening and monitoring but cannot replace comprehensive eye exams — consult an optometrist for diagnosis and conditions like strabismus, hyperopia or astigmatism.