Disclaimer

Platform sizes change

Resize presets and the sizes mentioned in guides reflect each platform's published guidance as we understood it on the “last checked” date shown. Platforms change their requirements without notice. Always confirm current specifications in the platform's own documentation before preparing images at scale.

Contrast results are not a full accessibility audit

The contrast checker applies the WCAG 2.x contrast formula correctly, but contrast is only one part of accessibility. Passing a ratio does not mean a page conforms to WCAG overall, and it is not legal advice.

Output varies by browser

Compression, conversion and resizing use your browser's built-in encoders. File sizes and visual results differ slightly between browsers and versions. Figures in worked examples illustrate the method; your numbers may differ.

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