Peripheral Vision Test
Keep your eyes on the centre and press when dots appear at the edges to map your side vision roughly.
Peripheral vision is everything you see outside the point you are looking at directly. It is less sharp than central vision but very sensitive to movement, and it is essential for walking, driving, sport and safely moving around. Some eye diseases, most notably glaucoma and retinitis pigmentosa, damage the peripheral field first, often without the person noticing for a long time, because the brain fills in the gaps and the other eye compensates.
In this test you keep your gaze on a central fixation point while small dots appear briefly at different angles and distances from the centre. You press a key or tap each time you see one. At the end, the tool shows a simple map of where you responded and where you missed dots. It is inspired by the principle of clinical perimetry, in which the visual field is measured point by point.
It is important to understand the limits. A computer screen covers only part of the visual field, the dots are not calibrated for brightness like a clinical perimeter, and eye movements cannot be monitored. This is a rough awareness check, not medical perimetry, and a normal result does not exclude glaucoma or other field defects. Formal visual field tests are part of a full eye examination.
How to use
- Sit centred in front of the screen at a close distance of about 30-40 cm so the dots reach further into your field.
- Dim the room slightly and remove glare; wear your usual glasses.
- Cover one eye with your palm without pressing; you will test each eye separately.
- Keep looking at the central point the whole time, even when you sense a dot at the edge.
- Press the key or tap the screen as soon as you notice a dot; do not guess when nothing appeared.
- Take short breaks if your eyes get tired, then repeat with the other eye and compare the maps.
Reading your result
A map with responses spread evenly across all directions suggests that, within the area the screen can cover, you noticed the stimuli well. A few scattered misses are normal and are often due to blinking, fatigue or a momentary lapse of attention.
Clusters of misses in the same region, especially if they appear again when you repeat the test, or a clear difference between the eyes, are reasons to book an eye examination with formal visual field testing. This is particularly important if you are over 40, have a family history of glaucoma, have diabetes or high myopia. A sudden loss of part of your field in daily life is an emergency.
Caution: Rough screening only, not medical perimetry and not a diagnosis. A sudden shadow, curtain or missing area in your vision requires same-day medical attention.
Frequently asked questions
Can this test detect glaucoma?
It cannot reliably detect or rule out glaucoma. Early glaucoma causes subtle defects that need calibrated perimetry plus examination of the optic nerve and eye pressure.
Why do I have to keep looking at the centre?
If you move your eyes towards a dot, you test central rather than peripheral vision, which makes the map meaningless.
Can exercises improve peripheral vision?
Attention exercises can improve how quickly you notice things at the edge of vision, but they cannot restore visual field lost to disease.