Are Online Eye Tests Accurate?
As digital health tools advance in 2026, online vision tests have become highly precise. However, the term "accuracy" depends entirely on what you are trying to measure. Online tests are exceptional for specific tasks, but they cannot replace a doctor.
What Online Tests Do Perfectly (Visual Acuity)
Online screenings, like the CorrectLens Vision Engine, are designed to measure Visual Acuity—the sharpness of your vision. They are highly accurate for:
- Tracking prescription changes between yearly doctor visits.
- Identifying immediate refractive errors (myopia or hyperopia).
- Screening for basic astigmatism.
- Replacing lost or broken glasses quickly using an existing baseline.
What Online Tests CANNOT Do (Eye Health)
Your eyes can have 20/20 vision and still be severely diseased. A computer screen cannot look inside your eye. Online tests cannot detect:
- Glaucoma: High pressure inside the eye that causes blind spots.
- Cataracts: Clouding of the internal lens.
- Macular Degeneration: Physical deterioration of the retina.
The Verdict: Use online tests for convenience, prescription tracking, and immediate screening. Visit a physical clinic annually for your comprehensive ocular health check.
Medical Disclaimer
This article is provided for educational and informational purposes only. CorrectLens does not provide medical diagnosis, treatment, or prescription services.
Online vision tests measure visual acuity (clarity of sight) and basic visual performance. They cannot detect eye diseases such as glaucoma, cataracts, macular degeneration, retinal disorders, or neurological conditions.
A comprehensive eye examination performed by a licensed eye care professional is required for medical diagnosis and prescription accuracy.