Eye Chart
The Eye Chart is a reference tool covering eye chart, snellen chart, snellen eye test, eye exam chart. Use the chart below to look up values instantly. Printable and downloadable versions are available on this page.
Snellen Eye Chart — Visual Acuity Reference
The Snellen chart, developed in 1862 by Dutch ophthalmologist Herman Snellen, remains the global standard for measuring distance visual acuity — used in clinical exams, DMV tests, military screenings, and school vision checks.
Snellen Visual Acuity Scale — Line by Line Reference
| Chart Line (Top to Bottom) | Snellen Notation | Letter Height at 20 Feet (mm) | What This Score Means |
|---|---|---|---|
| Line 1 (largest) | 20/200 | 87.8 mm | Legally blind threshold in the US. Can only see at 20 ft what a normal eye reads at 200 ft. |
| Line 2 | 20/100 | 43.9 mm | Very low vision. Significant difficulty with most daily tasks. |
| Line 3 | 20/70 | 30.7 mm | Moderate low vision. Reading print is very difficult. |
| Line 4 | 20/50 | 21.9 mm | Below the driving standard for most US states without correction. |
| Line 5 | 20/40 | 17.5 mm | Minimum for unrestricted driving in most US states. |
| Line 6 | 20/30 | 13.2 mm | Below average but functional for most daily tasks with some difficulty reading small print. |
| Line 7 | 20/25 | 11.0 mm | Near normal vision. Minor blur at small print sizes. |
| Line 8 | 20/20 | 8.75 mm | Normal vision. Standard benchmark — sees what an average healthy eye sees at 20 feet. |
| Line 9 | 20/15 | 6.6 mm | Better than normal. Very sharp distance vision. |
| Line 10 (smallest) | 20/10 | 4.4 mm | Excellent — twice as sharp as average. Common in children and young adults. |
Source: Herman Snellen 1862 — standard optometric visual acuity notation
Types of Eye Charts
Types of Eye Charts — When Each Is Used
| Chart Type | Description | Best Used For | Testing Distance |
|---|---|---|---|
| Snellen Chart | Rows of letters decreasing in size from top to bottom using optotypes | Standard adult distance vision testing in clinical and DMV settings | 20 feet (6 metres) |
| Tumbling E Chart | A letter E rotated in four different directions — patient indicates which way it faces | Children who cannot name letters and non-English speaking patients | 20 feet |
| Landolt C (Broken Ring) | A ring with a gap at different positions — patient indicates direction of gap | International standard that avoids alphabet literacy requirements | 20 feet |
| Lea Symbols Chart | Simple child-friendly symbols — apple, house, square, circle | Young children aged 2 to 5 years | 10 feet |
| ETDRS Chart (LogMAR) | Standardised rows with exactly 5 letters per row using uniform spacing | Clinical research, precise acuity measurement, and low vision assessment | 13 feet (4 metres) |
| Jaeger Near Vision Chart | Blocks of text in decreasing type sizes labelled J1 through J14 | Near and reading vision testing — presbyopia evaluation | 14 inches (35 cm) |
Source: American Academy of Ophthalmology
Visual Acuity Levels — What the Numbers Mean
Snellen notation expresses acuity as a fraction — the top number is always 20 (the testing distance in feet) and the bottom number is the distance at which a person with normal vision could read the same line.
Visual Acuity Levels and Practical Meaning
| Snellen Score | Category | What You Can and Cannot Do Without Correction |
|---|---|---|
| 20/10 | Eagle vision | Can read text at twice the distance that average eyes can. Rare in adults. |
| 20/15 | Better than normal | Very sharp. Minor difficulty with any visual task. |
| 20/20 | Normal | Can read standard print at 20 feet. The clinical average benchmark. |
| 20/30 to 20/40 | Mildly reduced | Can usually drive without correction in most US states. May need glasses for reading fine print. |
| 20/50 to 20/70 | Moderately reduced | Difficulty reading standard newspaper print without correction. Driving may require correction. |
| 20/100 to 20/200 | Significant impairment | Cannot read newsprint clearly. Difficulty recognising faces at a distance. |
| 20/200 — best corrected | Legal blindness threshold | Qualifies for legally blind classification in the United States. Maximum vision even with best corrective lenses. |
| Worse than 20/200 | Severe visual impairment | Very limited functional vision. Orientation and mobility training may be required. |
Source: US Social Security Administration and American Academy of Ophthalmology
Recommended Eye Exam Frequency
Eye Exam Schedule by Age Group — American Academy of Ophthalmology Guidelines
| Age Group | Recommended Frequency | Notes |
|---|---|---|
| Infants 6–12 months | At least one vision screening | Paediatrician screens for red reflex and alignment. |
| Children 1–5 years | At least once between ages 3–5 | Screen for amblyopia (lazy eye) and strabismus before school starts. |
| School age 6–17 years | Every 1–2 years | More frequently if corrective lenses are worn or vision problems are noted. |
| Adults 18–39 (no risk factors) | Every 2–3 years | Annual if contact lens wearer or risk factors present. |
| Adults 40–64 | Every 1–2 years | Presbyopia and early glaucoma screening become important. |
| Adults 65 and above | Every year | Age-related macular degeneration, glaucoma, and cataracts are more common. |
| Diabetic patients (any age) | At least every year or as directed by ophthalmologist | Annual dilated eye exam for diabetic retinopathy screening. |
Source: American Academy of Ophthalmology Preferred Practice Patterns
Online Vision Screener
Cover one eye, sit approximately 20 feet (or 6 feet from a small screen) away, and read the smallest line of letters you can make out clearly. This tool estimates rough visual acuity. Always see an eye doctor for a proper diagnosis.
Cover your LEFT eye and read the lowest line you can see clearly. Click that line.
E
F P
T O Z
L P E D
P E C F D
E D F C Z P
F E L O P Z D
D E F P O T E C
L E F O D P C T
F D P L T C E O
⚠️ This online screener is for awareness only. Screen calibration, ambient lighting, and viewing distance affect accuracy. It cannot test eye health, pressure, colour vision, or peripheral vision. Consult a licensed optometrist or ophthalmologist for a comprehensive eye examination.
Frequently Asked Questions
20/20 means you can see at 20 feet what a person with normal vision sees at 20 feet — it is the clinical standard for average healthy vision. It does not mean perfect vision — some people have 20/15 or even 20/10.
Legal blindness is defined as best-corrected visual acuity of 20/200 or worse in the better eye. This means that even with the best possible glasses or contact lenses the person can only see at 20 feet what a normal eye sees at 200 feet.
You can do a basic visual acuity screening using a printed or calibrated screen-based Snellen chart but a clinical exam by an optometrist or ophthalmologist tests far more than acuity — including eye pressure, retinal health, and binocular function. Online screens are for awareness only and cannot replace a professional examination.
20/20 is typically the eighth line from the top on a standard 10-line Snellen chart.
At 20/200 you can only see at 20 feet what a person with normal vision sees clearly from 200 feet. Close-up tasks may still be manageable but distance vision — reading street signs, recognising faces, watching TV from a normal distance — is very difficult.
Most US states require 20/40 or better in at least one eye (with or without correction) for unrestricted driving. Some states allow driving with worse acuity but require additional testing or impose driving restrictions.
Online eye tests can provide a rough indication of reduced distance acuity if your screen is calibrated correctly and you sit at the specified distance. They are not sufficiently accurate to replace a professional examination and cannot test eye health, pressure, or near vision.
20/15 means you can read at 20 feet what a normal eye only reads clearly from 15 feet — your vision is sharper than average. This is common in children and is generally considered excellent distance vision.