Text on Image Contrast Checker

Check your text placement

Click anywhere on the image (or drag) to position the text.

How it works: every letter of your text is sampled at its actual pixels — we read the image colors directly underneath the glyphs (text pixels excluded) and use the worst-case pair found. That worst-case ratio is what a reader with low vision actually experiences, so that is what WCAG measures. For plain color pairs, use the contrast checker; to see how the whole palette reads for color-blind users, try the color blindness simulator. To check an entire live page, run the free Accessibility Scanner.

The rules in short

• WCAG SC 1.4.3 requires 4.5:1 for normal text and 3:1 for large text (≥ 24 px regular or ≥ 18.66 px bold).
• SC 1.4.11 additionally requires 3:1 for meaningful UI parts and graphics.
• A gradient or busy photo can pass under half the letters and fail under the rest — always measure the worst case, not the average.
• If you fail: add a semi-transparent scrim behind the text, darken/lighten the image locally, or add a solid caption bar.