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Base64 Encode & Decode

Convert text or files to and from Base64 with full Unicode support and a URL-safe variant. The strings people Base64 are exactly the strings that shouldn't touch a third-party server — API credentials, auth headers, certificates. Here they never do.

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Why decode Base64 locally

Base64 isn't encryption — it's a reversible encoding, which means anything you paste into an online decoder is readable by whoever runs it. Basic-auth headers, JWT segments, SMTP credentials, and certificate blobs all travel as Base64, and they all get pasted into web decoders thousands of times a day. This tool runs the browser's own encoder locally, handles full Unicode (emoji and non-Latin scripts included, where many tools corrupt them), and supports the URL-safe alphabet used by JWTs and web APIs.