Add decode64.com — browser-only Base64 decoder & encoder

[zenopanda705-png]

Adding decode64.com to the Transformation section.

Why it fits:

• Free Base64 decoder/encoder — no server-side processing
• Runs 100% in the browser using native atob() / btoa()
• Supports Base64URL (JWT tokens), file drag-and-drop, UTF-8
• Single HTML file, zero dependencies, open source

Source: https://github.com/zenopanda705-png/base64-decoder

[github-actions]

Hey zenopanda705-png! Thanks for your submission! 🚀

To keep awesome-devtools instantly accessible for everyone, all tools must be:

• Browser-based — no downloads or native app installs
• Direct link — goes straight to the tool (not a multi-tool landing page)
• 100% free — no signups, trials, paywalls, or usage limits

Please make sure your PR meets these criteria. It may take some time for your submission to be reviewed — you can occasionally comment with a "bump" to bring more attention to it.

Thanks for contributing! 🙌