Free online vision test with 10 calibrated eye tests: 20/20 eye chart, color blindness plates, color threshold, D-15 hue, contrast sensitivity, astigmatism, Amsler grid, near vision, duochrome and visual field. Per-eye results and a downloadable report.
A free online vision test suite with ten screen-calibrated eye tests: a logMAR visual acuity chart (Sloan letters, Tumbling E or Landolt C) scored in 20/20, 6/6, decimal and logMAR; Ishihara-style color blindness plates generated from color-vision confusion lines; a Cambridge-style color threshold test that grades protan, deutan and tritan loss; a Farnsworth D-15 hue arrangement scored with the Vingrys & King-Smith method; a Pelli-Robson style contrast sensitivity test; an astigmatism clock dial that estimates the axis; a physically-sized Amsler grid; a near-vision reading card in true N-point print sizes; a red-green duochrome test; and a perimetry-style visual field test with blind-spot fixation monitoring. Calibrate once with any bank card and measure your viewing distance with your own blind spot, test each eye separately, then download or copy a report. Everything runs in your browser: no camera, no upload, no signup. It is an educational screening, not a medical diagnosis.
Your eyesight isn't one number. This suite covers the main functions an eye exam looks at: sharpness at distance (visual acuity) and up close (near vision), color vision (plates, a threshold test and a hue arrangement), contrast sensitivity, astigmatism, focus balance (duochrome), central vision (Amsler grid) and peripheral vision (visual field). Every test is drawn at a real physical size after a one-time screen calibration, and every result is saved per eye so you can compare right with left and track changes over time.
Features
Ten eye tests in one suite with a guided full-exam mode, per-eye results (right, left, both) and a report you can copy or download as a PNG.
Shared screen calibration: match any bank card (85.6 mm) or enter your screen diagonal, then set chart, desk and reading distances. Saved for next time.
Blind-spot distance measurement (the 'virtual chinrest' method from online vision research) finds your exact viewing distance.
logMAR visual acuity chart from 20/200 to 20/10, 5 symbols per line, letter-by-letter scoring, with Sloan letters, Tumbling E, 4-way or 8-way Landolt C, keyboard answers and a mirror mode for small rooms.
Warns when your screen can't draw a true 20/20 line at the chosen distance and tells you how far to step back.
13 color blindness plates built on protan, deutan and tritan confusion lines with randomized dot brightness, fresh numbers every run, and a protan-vs-deutan classification.
Plate review with a color-blindness simulator (Machado 2009) that shows how each plate looks to protan, deutan and tritan viewers.
Cambridge-style color threshold test: three interleaved staircases measure the smallest color difference you can see on each axis, in u'v' × 10⁻⁴ units.
Farnsworth D-15 style arrangement (standard and desaturated caps) scored with Vingrys & King-Smith confusion angle, C-index and S-index, plus the classic cap diagram.
Pelli-Robson style contrast sensitivity from 100% to 0.56% contrast in 0.15 log steps, with 'bit-stealing' color rendering for faint levels a normal 8-bit screen can't show.
Astigmatism clock dial: tap the darkest lines and get an axis estimate from the clinical 'rule of 30'.
Amsler grid sized to 1° per square at your reading distance, with wavy, blurry, missing and dark marking tools and a quadrant summary.
Near-vision reading card in true N5–N24 print sizes (≈ J1–J16) with random sentences so you can't memorize it.
Visual field screening to about 25° with the same reliability checks as a clinical perimeter: blind-spot fixation losses, false positives and false negatives.
Real Fullscreen API mode for distance tests and a result history stored only in your browser.
How to use Vision Test
1
Set up your screen (30 seconds)
Open Screen setup, hold a bank card against the display and resize the box until it matches. Then set how far you'll sit for the eye chart, your normal desk distance and your reading distance. The blind-spot method can measure the desk distance for you.
2
Pick a test or run the guided exam
Choose any of the ten tiles, or press 'Guided full exam' to go through acuity, near vision, astigmatism, duochrome, Amsler, contrast, color plates, D-15, color threshold and visual field in order (about 20 minutes).
3
Test one eye at a time
For acuity, near vision, astigmatism, duochrome, Amsler and the visual field, choose Right eye, cover your left eye with your palm, finish the test, then repeat for the left eye. Color tests are normally done with both eyes open.
4
Answer honestly and guess when unsure
Type or tap the letter, gap direction or number you see. Guessing is part of how acuity, contrast and threshold tests work, so give an answer rather than skipping. Use the keyboard (letters, arrows or Space) when you're across the room.
5
Read your results
Each test explains what your score means and when to see an eye-care professional. The Vision report table collects every result by eye, keeps a history, and can be copied as text or downloaded as a PNG to show your optometrist.
Common use cases
Checking your eyesight at home between eye exams, one eye at a time
Screening for red-green or blue-yellow color blindness and finding out whether it's protan or deutan
Checking whether your vision meets the usual 20/40 (6/12) driving standard before a license renewal
Watching for macular changes with a weekly Amsler grid if you're over 50 or have AMD in the family
Noticing presbyopia (needing reading glasses) with a true-size near-vision card
Checking contrast sensitivity if night driving or dim light has become harder
Teaching students how acuity, color vision, contrast and the visual field are measured
Detailed guide
Why calibration makes an online eye test accurate
A 20/20 letter is defined by the angle it covers at your eye: 5 arc-minutes. Getting that right online needs two numbers: how many pixels make a millimetre on your screen, and how far away you sit. The card step measures the first (every bank card, ID card and driving license is 85.6 mm wide). You can set the second by hand or measure it with your blind spot: everyone has a blind spot about 13.5° from where they look, so finding it on screen gives your distance, the 'virtual chinrest' method used in online vision research. The test also checks whether your screen has enough pixels to draw a real 20/20 line at your distance. If it doesn't, it tells you how far to step back.
How to read your visual acuity score
The acuity chart follows the logMAR design used in clinical trials: each line is 0.1 log units smaller than the last, with five symbols per line. You pass a line by reading three of the five, and every extra letter on the next line earns 0.02 logMAR, so the score is finer than whole lines. Results are shown in all four common notations.
Snellen (feet)
Snellen (meters)
Decimal
logMAR
What it means
20/10
6/3
2.0
-0.3
Exceptional, about twice the reference sharpness
20/16
6/4.8
1.25
-0.1
Better than 'normal', common in young adults
20/20
6/6
1.0
0.0
The reference standard for normal vision
20/40
6/12
0.5
0.3
Usual minimum for a driving license (both eyes)
20/70
6/21
0.29
0.54
Moderate visual impairment (WHO)
20/200
6/60
0.1
1.0
Legal blindness threshold in the US (best eye, corrected)
How the color blindness tests work
About 1 in 12 men and 1 in 200 women have a color vision deficiency, most often red-green. People with a deficiency confuse colors that lie on 'confusion lines' pointing to a copunctal point, and there are three of them: protan (red), deutan (green) and tritan (blue-yellow). The plates are generated from those lines, and every dot gets a random brightness, so the hidden number can only be seen through color. Graded red-green plates estimate severity, and two classification plates carry one digit on the protan line and one on the deutan line: which digit disappears tells the two types apart. The color threshold test goes further, like the Cambridge Color Test. It finds the smallest color difference you can see on each of the three axes using an adaptive staircase. The D-15 hue arrangement is scored with the Vingrys & King-Smith method, which reports a confusion angle, a severity (C-index) and a selectivity (S-index).
Type
What's affected
Approx. prevalence (men)
Best test here
Deutan (deuteranomaly / deuteranopia)
Green-sensitive cones
≈ 6%
Plates + color threshold
Protan (protanomaly / protanopia)
Red-sensitive cones; reds look darker
≈ 2%
Plates + color threshold
Tritan
Blue-sensitive cones
< 0.01% inherited (often acquired)
Color threshold + D-15
Contrast sensitivity: what a 20/20 chart misses
You can have 20/20 acuity and still struggle in fog, at dusk or with night driving, because acuity charts only use black-on-white letters. The contrast test shows groups of three letters that fade in 0.15 log-unit steps, like the Pelli-Robson chart, and your score is the log contrast sensitivity (logCS) of the faintest group you read. Ordinary 8-bit screens can't draw very faint gray steps, so the test uses 'bit-stealing': it nudges red, green and blue separately to get roughly ten times finer brightness levels.
logCS
Contrast read
Interpretation
1.80 – 2.25
1.6% – 0.56%
Excellent, typical of young healthy eyes
1.65 – 1.80
2.2% – 1.6%
Normal adult range
1.50 – 1.65
3.2% – 2.2%
Slightly reduced; common with age
1.00 – 1.50
10% – 3.2%
Visual impairment range; get an eye exam
below 1.00
more than 10%
Severe loss of contrast sensitivity
Astigmatism, the Amsler grid and the duochrome test
The astigmatism clock dial shows six bands of lines. If one direction looks darker or sharper, the eye focuses that meridian differently, and the 'rule of 30' (the lower clock number × 30) gives the approximate axis an optometrist would correct. The Amsler grid is sized so each square covers 1° of your central vision at your reading distance. Wavy, blurred, missing or dark areas can be an early sign of macular degeneration or macular edema, and you can mark each kind of change. The duochrome test uses chromatic aberration: red focuses slightly behind green in the eye, so if the black symbols look sharper on red, the eye is a little under-corrected; sharper on green, over-corrected.
Near vision and the visual field
The reading card uses true N-point print sizes (N8 is about newspaper text) drawn at physical size on your calibrated screen, rescaled to your reading distance. Needing N10 or larger after about age 40 usually points to presbyopia, which reading glasses correct. The visual field test flashes points out to about 25° while you look at a central cross. Like a clinical perimeter, it checks its own reliability: some dots are placed in your natural blind spot, so seeing them means your eye moved (a fixation loss); blank trials catch false positives, and bright re-tests catch false negatives. A cluster of missed points in one area is a reason to get formal perimetry.
Limits of screen-based eye tests
Screens vary in brightness, color accuracy and gamma. Rooms vary in lighting, and people don't sit perfectly still. That's why each result here is a screening, not a diagnosis, and why the tool marks results taken before calibration. A clinic uses standardized charts, lighting and instruments, and it also checks eye pressure, the retina and the optic nerve, which no online test can do. Use this suite to notice changes and to know when to book an appointment. Sudden vision loss, new distortion, flashes, a curtain over your vision or a painful red eye need urgent care.
Frequently asked questions
Is this online vision test accurate?
It's as accurate as a screen test can be. Symbols are drawn at real physical size after you calibrate with a bank card and set your distance, acuity is scored letter by letter on a logMAR chart, and color tests are built on color-vision confusion lines. It's still a screening, not a diagnosis: screen brightness, color accuracy and lighting affect results. See an optometrist to confirm anything that looks abnormal.
How do I test my eyesight online for 20/20 vision?
Open Screen setup and match the box to a bank card, then set the chart distance (3 m / 10 ft is ideal). Choose Visual acuity, pick the right eye, cover your left eye and read the symbols, typing letters or pressing arrows. The smallest line where you get 3 of 5 right, plus extra letters on the next line, becomes your score in 20/20, 6/6, decimal and logMAR. Then repeat with the left eye.
Why do I need a bank card for an eye test?
Every bank card, ID card and driving license is exactly 85.6 mm wide. Matching an on-screen box to it tells the test how many pixels make a millimetre on your display, so letters can be drawn at the exact size for each line. Without it, an online eye chart can be 30–60% off on laptops and phones.
What if my room is too small to stand 3 meters away?
Sit closer and set the real distance in Screen setup: the chart rescales. The test warns you if your screen can't draw a true 20/20 letter at that distance. Or use Mirror mode: sit beside the screen, look at it in a mirror, and set the distance to the full path (you → mirror → screen). The chart is flipped so it reads correctly in the mirror.
How does the color blindness test tell protan from deutan?
Two classification plates each hide a two-digit number: one digit is drawn along the protan confusion line and the other along the deutan line. People with protan deficiency lose one digit, and people with deutan deficiency lose the other. The color threshold test confirms it by measuring how much color difference you need on each axis.
Can I trust color blind test results on a phone or laptop screen?
They're a good screen, but not a diagnosis. Turn off Night Shift, Night Light, blue-light filters and color filters, set brightness to medium-high and test in normal light. If the demonstration plate is missed, the test warns that your screen settings are the problem. An eye doctor can confirm with printed plates or an anomaloscope.
What is the color threshold (Cambridge-style) test?
A ring with a gap is hidden in a field of dots that differ from the background only in color, along the protan, deutan or tritan axis. You say which way the gap faces, and three adaptive staircases find the smallest difference you can see on each axis. Results are in CIE u'v' × 10⁻⁴ units, with typical normal limits around 100 for red-green and 150 for blue-yellow.
How is the D-15 color arrangement test scored?
It uses the Vingrys & King-Smith method. The color steps between the caps in your order are turned into a confusion angle (which axis the errors run along), a C-index (severity, where 1.0 is perfect and above 1.6 fails) and an S-index (how selective the pattern is). The classic cap diagram shows your crossing lines against the protan, deutan and tritan axes. The desaturated version catches milder defects.
What does my contrast sensitivity score (logCS) mean?
logCS is log₁₀(1 ÷ the faintest contrast you read). A score of 2.0 means you read letters at 1% contrast. Normal adults score about 1.65–2.0; 1.5–1.65 is slightly reduced; below 1.5 is in the impairment range, which can come from cataract, glaucoma, macular disease or an old prescription, and makes night driving harder.
How do I read the astigmatism test?
Cover one eye and look at the clock dial from 1–2 m. If all six bands look equally dark, there's no obvious astigmatism. If one band looks darker or sharper, tap it: the tool estimates the axis with the 'rule of 30' (the lower clock number × 30°). Only a refraction can measure how strong the astigmatism is.
How often should I use the Amsler grid?
Eye doctors usually suggest once a week, one eye at a time, if you have macular degeneration, diabetes, high myopia or AMD in the family, or if you're over 50. Hold the screen at your reading distance with reading glasses on and look only at the center dot. Any new wavy, blurred, missing or dark area should be checked by an eye doctor within days.
How does the near vision (reading) test work?
It shows random sentences in true print sizes from N24 down to N5 (about J16 to J1), drawn at physical size on your calibrated screen and adjusted for your reading distance. Tap the smallest line you can read fluently. N5–N6 is normal for young adults; needing N10 or larger after 40 usually means presbyopia, which reading glasses fix.
What does the red-green duochrome test tell me?
Red light focuses slightly behind green inside the eye. If black symbols look sharper on the red side, the eye is probably a little under-corrected for distance. If they look sharper on green, it's over-corrected (too much minus), which can cause strain. Equal means balanced. It works even if you're color blind, because you compare sharpness, not color.
How does the online visual field test work?
Look only at the center cross and press Space or tap whenever you notice a dot. Points are flashed out to about 25° depending on your screen. Like a clinical perimeter it measures reliability: dots placed in your natural blind spot catch eye movements, blank trials catch false presses, and bright re-tests catch missed responses. The result map shows seen and missed points by quadrant.
What is the blind spot distance measurement?
Each eye has a blind spot about 13.5° to the side of where you look, where the optic nerve leaves the eye. With your right eye closed, you watch a square while a red dot moves left, and press when it disappears. Knowing that angle and the dot's position gives your exact viewing distance. Researchers use this 'virtual chinrest' method in online vision studies.
Should I test each eye separately?
Yes. The stronger eye can hide a problem in the weaker one when both are open, and many conditions affect one eye first. Acuity, near vision, astigmatism, duochrome, Amsler and visual field are all tested per eye, and the report shows right and left side by side. Color blindness is usually inherited and affects both eyes equally, so those tests default to both eyes.
Can this online eye test replace an eye exam or give me a prescription?
No. It can't measure your lens power, check eye pressure, or look at your retina and optic nerve, which is how glaucoma, diabetic eye disease and many other conditions are found. Use it to notice changes and decide when to book an exam. Adults should have a full eye exam every 1–2 years, or sooner if something changes.
Is my data private? Does it use my camera?
The camera is never used and nothing is uploaded. Calibration and results are saved only in your browser's local storage so you can compare over time. You can copy or download your report yourself, and the Reset button deletes everything.
What vision do I need to drive?
Most licensing rules need about 20/40 (6/12, decimal 0.5) with both eyes open, wearing glasses if needed, plus an adequate visual field. The exact rules vary by country and state. This test shows your 20/x score per eye and a visual field screen, but only an official test counts for a license.
When should I see an eye doctor straight away?
Get same-day care for sudden vision loss or blur, a new dark area or distortion in the center of your vision, a shower of new floaters or flashes, a curtain or shadow across your vision, double vision, or a painful red eye. Don't wait for an online test to confirm these.
