WolfChart is a professional tool for measuring visual acuity and performing other distance refraction tests. It is NOT a substitute for an eye examination with a qualified optometrist or eye doctor. If you are experiencing problems with your eyes or vision, do not use WolfChart; instead consult an optometrist or doctor as soon as possible.
The latest version of WolfChart is online now. The link will open a new tab in your browser.
WolfChart is 100% javascript, so it works without an internet connection once open in your browser. You WILL need to first download it from the internet though. Save the archive somewhere nice, unzip it and read the readme file.