CodexTheme Tools

CodexTheme Tools is a free, unofficial theme builder for the Codex Desktop app. Pick any image and the builder derives a color theme in your browser, without uploading the image. You can preview the theme across five workspace views, check text readability before exporting, and download data-only theme files. There is no sign-up. The site also has a library of ready-made themes and troubleshooting answers for when a theme does not apply as expected.