Create an accurately scaled eye chart for your room and print it on ordinary paper. Choose Snellen letters, a tumbling E or picture symbols, set a viewing distance of 10 or 20 feet (3 or 6 meters), and download a PDF with a built-in ruler so you can check it printed at true size.
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Screening only. A printed chart gives a rough check of distance visual acuity. It cannot diagnose eye conditions or replace an eye exam by an optometrist or ophthalmologist.
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How to use the Printable Eye Chart
Pick the chart type: Snellen letters for adults, tumbling E or picture symbols for children or people who do not read Latin letters.
Choose your viewing distance. 10 feet (3 m) fits most rooms; 20 feet (6 m) is the classic clinic distance and needs two pages.
Select paper size and the smallest line, then check the preview. Tick Add an answer key page if a helper will run the test.
Download PDF and print it at 100% or Actual size. Measure the black bar at the bottom: it must be exactly 100 mm.
Hang the chart at eye level in good light, stand at the exact distance, cover one eye and read down to the smallest line you can.
Letter sizes for each line
Symbol height = distance × tan(5′) × D ÷ 20, where D is the Snellen denominator and tan(5′) ≈ 0.0014544. Stroke width and gaps are one fifth of the height. The table shows the heights this generator prints.
Snellen (ft)
Metric
Decimal
LogMAR
Height at 10 ft
Height at 20 ft
Height at 3 m
Height at 6 m
20/200
6/60
0.1
1.0
44.3 mm
88.7 mm
43.6 mm
87.3 mm
20/100
6/30
0.2
0.7
22.2 mm
44.3 mm
21.8 mm
43.6 mm
20/70
6/21
0.29
0.54
15.5 mm
31.0 mm
15.3 mm
30.5 mm
20/50
6/15
0.4
0.4
11.1 mm
22.2 mm
10.9 mm
21.8 mm
20/40
6/12
0.5
0.3
8.87 mm
17.7 mm
8.73 mm
17.5 mm
20/30
6/9
0.67
0.18
6.65 mm
13.3 mm
6.54 mm
13.1 mm
20/25
6/7.5
0.8
0.1
5.54 mm
11.1 mm
5.45 mm
10.9 mm
20/20
6/6
1.0
0.0
4.43 mm
8.87 mm
4.36 mm
8.73 mm
20/15
6/4.5
1.33
−0.12
3.32 mm
6.65 mm
3.27 mm
6.54 mm
20/10
6/3
2.0
−0.3
2.22 mm
4.43 mm
2.18 mm
4.36 mm
Setting up a home vision check
Print and verify: print at 100% and measure the 100 mm bar with a ruler. A chart printed at 97% makes every line about 3% smaller.
Light: the chart should be evenly lit with no glare, ideally with the light behind or beside the person being tested.
Height and distance: hang the 20/20 line at roughly eye level and measure the distance from the eyes to the paper with a tape measure.
One eye at a time: cover the other eye with the palm or an occluder, without pressing on it, and keep glasses on if they are worn for distance.
Children: practise tumbling E or picture symbols up close first so they know what to say or point to; use a helper with the answer key.
Shuffle between tests so nobody can memorize the lines.
Frequently asked questions
How big should the letters be on a printed eye chart?
On a standard chart a 20/20 (6/6) letter spans 5 minutes of arc at the viewer's eye, with strokes 1 minute of arc thick. The height is distance × tan(5′) × (Snellen denominator ÷ 20). At 20 feet (6.1 m) a 20/20 letter is 8.87 mm tall and a 20/200 letter 88.7 mm; at 10 feet everything is half that size. This generator calculates every line from that formula.
Why must I print at 100% scale?
Printers often shrink pages to fit their margins, which makes every letter smaller and the chart read harder than it should. In the print dialog choose Actual size or 100% (turn off Fit to page), then measure the 100 mm bar at the bottom of the page. If it is not 100 mm, the chart is not accurate for the distance printed on it.
What distance should I use: 10 feet or 20 feet?
Both give the same result when the chart is sized for that distance. 20 feet (6 m) is the traditional distance because the eye focuses almost as it does for far objects, but many rooms are too small. A 10 ft (3 m) chart is half the size and fits on a single sheet; just make sure you stand exactly 10 feet away, measured from your eyes to the paper.
What is the difference between Snellen, tumbling E and LEA-style charts?
A Snellen chart uses letters; this one uses the ten Sloan letters drawn on a 5 × 5 grid so they are similarly easy to read. A tumbling E chart shows only the letter E rotated right, left, up or down, and the person points the way the bars face. Picture symbol charts use simple shapes (circle, square, house, apple) that young children can name or match, in the style of LEA symbols. All use the same line sizes.
How do I read the result?
Test one eye at a time with your usual distance glasses on. The result is the smallest line where you read more than half the symbols correctly, written as the label on that line, for example 20/30 or 6/9. 20/20 is standard normal acuity; many US driving tests require about 20/40 with both eyes. If a line is worse than you expect or the eyes differ by two lines or more, see an eye care professional.
Can I use this chart for an official test?
No. A home-printed chart is useful for screening and practice, but lighting, print quality and distance are not controlled the way they are in a clinic, and it cannot check eye health. Driving licences, school records and prescriptions need a test by a qualified professional.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.