Base64 Encoding in JavaScript
Learn Base64 encoding and decoding in JavaScript. Use btoa(), atob(), Buffer, and handle Unicode characters correctly.
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JavaScript provides built-in functions for Base64 encoding, but handling Unicode requires special attention.
Browser: btoa() and atob()
btoa() encodes a string to Base64, atob() decodes. Note: These only work with ASCII characters. For Unicode, encode to UTF-8 first.
Node.js: Buffer
Use Buffer.from(string).toString("base64") to encode and Buffer.from(base64, "base64").toString() to decode. Buffer handles Unicode correctly.
Handling Unicode
In browsers: encodeURIComponent() + btoa() for encoding, atob() + decodeURIComponent() for decoding Unicode strings safely.
Summary
Test your JavaScript Base64 encoding with our online Base64 tool.