| 0.00 (20/20.1) | |
| -0.10 (20/15.9) | |
| -0.20 (20/12.6) | |
| -0.30 (20/10.0) | |
| -0.40 (20/7.96) | |
| -0.51 (20/6.32) | |
| -0.60 (20/5.01) | |
| -0.69 (20/4.05) | |
| -0.81 (20/3.10) | |
| -0.92 (20/2.38) | |
| -1.02 (20/1.91) | |
| -1.08 (20/1.67) | |
| -1.14 (20/1.43) | |
| -1.22 (20/1.19) | |
| -1.32 (20/.955) | |
| -1.45 (20/.716) | |
| -1.62 (20/.477) |
Print this chart and view it at 20 feet. Acuities are given as LogMAR and (Snellen). For viewing from 10 feet, add +0.3 to the LogMAR number and halve the Snellen fraction.
Opotypes and font sizes are chosen to best survive quantization onto a 1200dpi printer grid; nonetheless, most laser printers will produce visible distortion on the -1.22 line and below. Use the following line as a reference for tweaking your quality settings:
You have healthy visual acuity if you can read the first line at the prescribed distance. The overwhelming majority of people will be unable to read beyond the first four. There are anecdotal accounts of humans with 20/1 vision; such people, if they indeed exist, could read the -1.22 line. The remaining lines are likely beyond the ability of any living person.
By @dfranke.