Prism

Prism is a menu-bar pipette that samples any two pixels on screen and tells you, instantly, whether the contrast passes WCAG. Built for designers who check ratios a hundred times a day.

Checking contrast meant leaving my design tool, pasting hex codes into a website, and squinting at a pass/fail badge. Prism collapses that into a keystroke: pick two colours anywhere on screen and read the ratio in the menu bar.

It samples real screen pixels with Core Graphics, so it works against anything — a live website, a mockup, a photo. The whole UI is one popover: two swatches, the ratio, and the AA/AAA verdicts for normal and large text.

A focused tool, retired the moment the platform made it redundant.

Prism is archived now — the system colour-picker caught up and I’d rather point people there than maintain a tool the OS made redundant. I’m leaving it up because the source is a tidy little example of a focused AppKit utility.