Guides

Understanding Base64 Encoding and Decoding

CodeUtilityKit Team··6 min read

What is Base64?

Base64 is a binary-to-text encoding scheme that represents binary data using 64 ASCII characters. It converts binary data into a format that can be safely transmitted over text-based protocols.

Why Use Base64?

Base64 is commonly used for:

  • Embedding binary data (images) in HTML/CSS
  • Encoding data in JWT tokens
  • Transmitting binary data over email (MIME)
  • Storing binary data in JSON
  • HTTP Basic Authentication headers

How Base64 Works

Base64 takes groups of 3 bytes (24 bits) and encodes them as 4 ASCII characters from a 64-character alphabet (A-Z, a-z, 0-9, +, /). The = sign is used for padding.

Base64 vs Encryption

IMPORTANT: Base64 is NOT encryption! It is easily reversible and provides no security. Never use it to secure sensitive data.

Using Base64 in JavaScript

Encoding: btoa('Hello, World!') Decoding: atob('SGVsbG8sIFdvcmxkIQ==')

Try Our Base64 Tools

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