Base64 Encoding Explained with Examples

What is Base64?

Base64 is a binary-to-text encoding scheme. It represents binary data in an ASCII string format by translating it into a radix-64 representation.

The name comes from the fact that it uses exactly 64 characters to represent data: `A-Z`, `a-z`, `0-9`, `+`, and `/`, with `=` used for padding.

When Should You Use Base64?

Base64 is widely used for:

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JavaScript Encoding & Decoding

Modern browsers provide native functions for Base64:

// Encoding a string
const original = "Hello World!";
const encoded = btoa(original);
console.log(encoded); // "SGVsbG8gV29ybGQh"

// Decoding a string
const decoded = atob(encoded);
console.log(decoded); // "Hello World!"

Note that `btoa` and `atob` only support ASCII characters. For Unicode/UTF-8 strings, you need a helper function to avoid errors.

Try our [Base64 Encoder/Decoder](/tools/base64-encoder) to safely encode and decode text, including full UTF-8 Unicode characters.