Visual Acuity Testing

This page includes instructions for downloading and printing an eye chart, or for using a mobile device.

Home Eye Test - Printed Chart


It is possible to do some basic testing of your vision and the vision of your family members and friends at home. Home eye testing is not a substitute for a complete medical eye examination by an ophthalmologist. Testing your vision at home will not be as accurate as what your ophthalmologist can do. But home eye testing could help you discover a problem that requires professional attention.

What You Need to Test Your Vision at Home
  • A computer with a printer to download and print PDF's
  • Something to cover the eye, like a paper cup or facial tissue
  • Tape or tack to hang the test chart on the wall
  • A yardstick, tape measure, or ruler
  • A flashlight, if available
  • A well-lighted room at least 10 feet long
  • The correct testing chart

Mobile Device Test


This test is intended as a convenient screener for visual acuity to be used on a mobile device and should not be used as a replacement for in-office testing. Evidence for smartphone apps for Snellen visual acuity is limited, and currently no app has been found to be accurate to within at least one line of formal visual acuity testing (and further validation is required).

  • Use this page on your cell phone to ensure correct image size.
  • Ensure proper room lighting and set phone brightness to 100%.
  • Hold the screen 4 feet (1.2 m) from the person.
  • Test each eye independently. The patient should completely cover the opposite eye.
  • Record the lowest line number (#1 - 11) the person can read correctly.