How EyeCheck Tests Your Vision
EyeCheck.app screens your vision in the browser using standardised, clinically based eye chart methods. This page explains what each test measures, how we score results, what an online screening can and can’t tell you, and how we handle your data.
What EyeCheck is
A digital screening tool, based on clinically validated methods, that flags possible vision problems so you know when to see an eye doctor.
What EyeCheck is not
Not a diagnosis, prescription or full eye exam. Results are a guideline only and can’t be guaranteed to be 100% accurate.
What each test measures
Visual acuity screening picks up common problems such as myopia (short-sightedness), which is projected to affect around half the world’s population by 2050.1
| Test | What it measures | Method | Limits |
|---|---|---|---|
| Visual acuity | How clearly each eye sees detail at a distance. | Picture shapes for ages 3–7; Landolt C rings (a ring with a gap in one of four directions) for ages 8 and up, viewed from 3 m. | Doesn’t check eye pressure, eye health or the need for a specific prescription. |
How we calibrate your screen and distance
The test only works if each symbol appears at the right size from where you sit. Before you start, we ask for:
- A screen of at least 33 cm (13″). Symbols are drawn at precise sizes; smaller screens can’t show the smallest lines accurately.
- Sit 3 m (10 ft) away. Symbols are sized for this distance. Sitting closer makes the test easier and the result less accurate.
- A wireless mouse. So you can answer without moving closer to the screen.
- Good, even lighting. Glare or dim light can change your result.
- One eye at a time. Each eye is screened separately so a problem in one eye isn’t hidden by the other.
Scoring and referral
Each eye gets one of two results:
- Pass. Your vision is within the normal range for your age.
- Refer. You may benefit from a more comprehensive eye exam by an eye care professional.
Accuracy and limits
EyeCheck.app is based on clinically validated screening methods. Like any screening, it can miss problems or flag ones that aren’t there.
Things that affect accuracy:
- Screen size and brightness
- Viewing distance
- Lighting and glare
- How well a young child understands and cooperates
- Wearing (or not wearing) your usual glasses
The technology behind EyeCheck
EyeCheck.app runs entirely in your web browser. There’s nothing to install, and the test draws each symbol at a precise size for your screen and distance, using the same principles as a printed eye chart.
Because it only needs a computer and an internet connection, schools, clinics and charities can screen many people quickly, including communities that don’t have easy access to an eye doctor.
Screening for schools →Charity support →Start a free eye test
Your data
Personal information is kept for a maximum of 7 days to deliver your results. Your email is kept longer only if you opt in to reminders. You can delete your data at any time from your results page or by emailing support@eyecheck.app. Read our privacy policy.
Sources
- Holden BA et al. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology, 2016.