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Copy ready-to-use Base64 encode/decode code for your language.

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What is Base64?

Base64 is a way to represent any binary data — text, images, files — using only 64 safe characters (A–Z, a–z, 0–9, plus two symbols). It lets you embed or transmit binary content through systems that only expect text, such as JSON payloads, data URIs, email, and URLs.

Standard Base64 vs URL-safe Base64

Standard Base64 uses + and /, which have special meaning in URLs. URL-safe Base64 replaces them with - and _ and usually removes the = padding, so the value can be dropped into a URL, filename, or JWT without escaping. This tool converts between the two losslessly.

Why Base64 makes files larger

Base64 encodes every 3 bytes as 4 characters, so encoded output is about 33% larger than the original. That's the trade-off for text-safe transport — the inspector shows the exact expansion for your input.

Your data stays in your browser

This tool uses your browser's built-in APIs. Nothing is uploaded, stored, logged, or tracked. There is no account, no watermark, and no external service in the middle — you can even use it offline.