🔐 Base64 Encode & Decode

What is Base64?

Base64 is a binary-to-text encoding scheme that represents binary data as ASCII characters. It's commonly used to embed images in HTML/CSS, encode email attachments, transmit data in URLs, and store binary data in JSON. Every 3 bytes of input become 4 Base64 characters.

Understanding Base64 Encoding

Base64 is a binary-to-text encoding scheme that converts binary data into a set of 64 printable ASCII characters. It's used whenever binary data needs to be transmitted over text-based protocols like HTTP, email (MIME), or stored in text formats like JSON and XML.

How Base64 Works

Base64 takes every 3 bytes (24 bits) of input and splits them into 4 groups of 6 bits. Each 6-bit group maps to one of 64 characters (A-Z, a-z, 0-9, +, /). If the input length isn't divisible by 3, padding characters (=) are added. This means Base64 output is always about 33% larger than the original data.

Common Uses

• Data URIs — Embedding images directly in HTML/CSS (e.g., data:image/png;base64,...)
• API Authentication — HTTP Basic Auth encodes credentials as Base64
• Email Attachments — MIME encoding uses Base64 for binary attachments
• JWT Tokens — Header and payload are Base64URL-encoded
• Storing binary in JSON — Since JSON doesn't support binary, Base64 is used

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