How it works
Pixel density (PPI) is the number of pixels per inch along the diagonal —
higher means sharper text. Retina distance is the distance at which a person
with 20/20 vision can no longer distinguish individual pixels, because each pixel subtends less
than one arc-minute of your visual field. Sit closer than that and you may notice the pixel
grid; sit at or beyond it and the image looks continuous.
That single number explains the whole resolution debate: a 27″ 4K monitor (~163 PPI) is
effectively pixel-free from a normal desk distance, while a 32″ 1080p panel (~69 PPI) would
need you to sit nearly a metre back before the pixels vanish — which is why it looks soft up
close. The recommended distance never drops below an arm’s length, the ergonomic floor for eye
comfort.
Next steps
Shopping for a sharper panel? Browse our monitor reviews and
buying guides, and pair your pick with a monitor arm
to set the exact height and depth this tool recommends.