A collection of interactive tools to help you explore visual acuity, colour vision, screen comfort and common eye conditions — built by Janine van Staden Optometrists to support (not replace) professional eye care.
Tap any card to open that tool right here on the page.
The Snellen chart is the classic letter chart used to measure visual acuity — how clearly you can see at a distance. Rows of letters get smaller from top to bottom, and each row is labelled with a fraction (like 6/12 or 6/6) comparing what you can read at 6 metres to what someone with "normal" vision can read from the same distance.
The Amsler grid is a simple grid of straight lines with a dot in the centre, used to check the macula — the part of the retina responsible for sharp, central vision. Worn with reading glasses if needed, held about 30 cm away with one eye covered, a person focuses on the centre dot and notes whether any lines appear wavy, blurred, distorted or missing.
Look at each dot pattern in good, natural lighting and type the number you see. These are original, simplified patterns inspired by clinical colour-vision plates — not a diagnostic Ishihara test.
Sitting too close to a screen for long periods contributes to digital eye strain. Choose your device to get a comfortable, evidence-informed viewing distance.
Paste in your own text — a menu, a sign, a document — and preview how it might look to someone with reduced visual acuity or low contrast sensitivity.
Select a condition to see how a typical outdoor scene might look with that visual impairment. Every person's experience differs — this is illustrative, not exact.
For signage, presentations or large-print documents: tell us the viewing distance and how comfortable the text needs to be, and we'll suggest a minimum font size.
These tools are a starting point. A comprehensive eye exam with Janine van Staden Optometrists picks up what a screen never can.
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