Eye test
A quick check of your sight and colours at home, so you know when it is time to visit an eye doctor.
PrivateNo uploadsRuns in your browserSize your screen
Screens differ, so the letters need a real size to be fair. Hold any bank, ID or store card flat against the screen and move the slider until the outline matches its edges.
Match the long side first, then check the short side lines up too.
How far will you sit for the letter test?
Measure it with a tape if you can. Farther is better for distance sight; ask someone to press the buttons, or use a wireless keyboard.
How to check your eyes at home
Size your screen
Hold a bank or ID card to the screen and match the outline. Then pick how far you will sit.
Test one eye at a time
Cover one eye and say which way each E points, line by line. Then do the dial and the Amsler grid for each eye.
Check colour and contrast
Read the numbers in the dot plates and the fading letters with both eyes, then save or print your results.
Good to know
- Do the tests in good, even light without glare on the screen.
- Wear your usual glasses or lenses: the test shows how well you see with them.
- The farther you sit for the letter test, the finer it can measure. Ask someone to press the buttons for you.
- The screen size is remembered on this device, so next time you can start straight away.
- Ctrl+C with nothing selected copies all your results.
Questions people ask
Can I test my eyes online?
You can check the basics at home: how sharp your sight is in each eye, red-green colour vision, signs of astigmatism and changes in the centre of your sight with the Amsler grid. It is a screening aid. Only an optometrist or eye doctor can measure your glasses power and check the health of your eyes.
What does 6/6 or 20/20 vision mean?
It means you read at 6 metres (20 feet) what a person with normal sight reads at 6 metres. 6/12 (20/40) means you need to be at 6 metres to read what normal sight reads from 12. The decimal form is the same fraction: 6/6 is 1.0 and 6/12 is 0.5.
Why do I need a card to size the screen?
The letters must be a real size, and every screen shows a pixel at a different size. A bank, ID or store card is the same size all over the world (85.6 by 54 mm), so matching it tells the page how big a millimetre is on your screen.
How accurate is the colour vision test?
The plates are made fresh in your browser with red and green dots of the same brightness, so only colour shows the number. If you miss several plates you may have red-green colour weakness, which is common in men. Screens differ, so an eye doctor should confirm it with printed plates.
What does it mean if some lines on the dial look darker?
If lines in one direction look darker or sharper than the rest, it is a sign of astigmatism: the front of the eye is shaped more like a rugby ball than a football. It is very common and glasses or contact lenses correct it.
What is the Amsler grid for?
It checks the centre of your sight. Wavy, bent, blurred or missing lines can be an early sign of a problem with the macula, the part of the eye used for reading and faces. If you see that, and especially if it is new, see an eye doctor soon.
How often should I have a real eye test?
Most adults should have a full eye test every one to two years, and children before school and then as advised. See an eye doctor straight away for sudden loss of sight, flashes, a curtain over your sight, or a painful red eye.