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From: Steve Green
Date: Jun 12, 2025 7:57AM

As long as it's real text rather than an image of text, then yes. Here are a couple of options.



* Brandwood checker for real text overlaying images - https://www.brandwood.com/a11y/. This allows you to upload an image and set the colour, size and position of the text. It only takes measurements at 8 points, which isn’t terribly useful, but it could be ok for background gradients or textures rather than images.

One issue is that if you change the text colour, the results do not update unless you change the font size or move the text. I reported this to the developer 6 years ago, but they haven’t fixed it.

* Firefox - https://firefox-source-docs.mozilla.org/devtools-user/accessibility_inspector/index.html#color-contrast. This built-in tool takes a brute force approach of measuring the contrast between every pixel in a piece of text (including ascenders and descenders) and every adjacent colour in the background. If the contrast is insufficient even for just one pixel, it reports a failure. Unfortunately, it does not tell you which pixel(s) have insufficient contrast or how many.

To use it, right-click on the piece of text you want to check, then select Inspect Accessibility Properties from the dropdown menu.

The Accessibility Inspector will open, and the relevant node will be highlighted. Expand the node and select the text leaf. The colour contrast ratio will be displayed in the right-hand panel.

Steve Green
Managing Director
Test Partners Ltd