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Monitor Sharpness and Viewing Distance Calculator
See how sharp a monitor really looks from where you sit, and the distance where its pixels disappear.
OSHA suggests sitting at least about 50 cm (20 inches) from your monitor.
Popular monitors from your seat
| Monitor | PPI | Pixels per degree | Pixels vanish at |
|---|---|---|---|
| 24" 1920 × 1080 | |||
| 27" 2560 × 1440 | |||
| 27" 3840 × 2160 | |||
| 32" 3840 × 2160 | |||
| 34" 3440 × 1440 | |||
| 49" 5120 × 1440 |
How we work it out
PPI comes from the screen's diagonal size and resolution. Pixels per degree measures how many pixels fit into one degree of your vision at your distance, so it accounts for both the screen and where you sit. "Pixels vanish at" is the distance where the screen reaches about 60 pixels per degree, the classic benchmark for 20/20 vision. "Fully sharp at" uses about 94 pixels per degree, the level a 2025 University of Cambridge study found people can still see.
- Below 40: you can clearly see pixels and jagged text.
- 40 to 60: looks fine for most games, with some softness on text.
- 60 to 94: sharp for normal vision.
- 94 and above: more detail than most eyes can see from here.
Frequently asked questions
What is PPI?
Pixels per inch: how many pixels fit along one inch of the screen. More pixels per inch means a sharper picture at the same distance. A 27 inch 1440p monitor is about 109 PPI, and a 27 inch 4K monitor is about 163 PPI.
Why does viewing distance matter so much?
Sharpness depends on how big each pixel looks from where you sit, not just on the monitor. Sit closer and the same pixels look bigger. That is why this calculator measures pixels per degree of your vision, which takes both the screen and your distance into account.
What do 60 and 94 pixels per degree mean?
About 60 pixels per degree is the classic benchmark for 20/20 vision, the point where a person with normal vision stops seeing individual pixels. A 2025 study from the University of Cambridge found that people can see detail up to about 94 pixels per degree, so a screen can still look sharper beyond 60.
How far should I sit from my monitor?
The US Occupational Safety and Health Administration (OSHA) suggests placing your monitor at least about 20 inches (50 cm) away, roughly at arm's length, and directly in front of you. Beyond that, choose a distance where you can read text without leaning forward.
Is 4K worth it on a 27 inch monitor?
At a normal desk distance, 27 inch 4K is noticeably sharper than 1440p, especially for text. It also asks far more of your graphics card in games. If you mainly play fast games at high frame rates, 1440p is often the better balance.
Choosing a monitor? See our monitor guides, or try the bottleneck calculator to check your PC can drive it.