# Contrast Grid Paste a palette and score every text-on-background colour pair against WCAG at once — a full matrix of contrast ratios with AA/AAA verdicts. Everything is computed in your browser. ### How it works Every colour is paired with every other as *text on background*, and each pair's **WCAG contrast ratio** is computed from relative luminance. A ratio of **4.5:1** is the AA threshold for normal text (3:1 for large text — 18.66px bold or 24px), and **7:1** is AAA. Colours are parsed with a canvas context, so any CSS colour works: `#hex`, `rgb()`, or names like `rebeccapurple`. Switch between normal and large-text thresholds to see how the verdicts change. --- *Source: [ocxly.com/contrast-grid.html](https://ocxly.com/contrast-grid.html) — OCXLY, free 100% client-side privacy-first tools. Free WCAG contrast grid — score every text-on-background pair in a palette for AA/AAA, entirely in your browser.*