Module base64

Base64 encoding and decoding.

• Crate ::base64.
• docs.rs
• crates.io
• GitHub

base64 provides encoding and decoding for Base64, a binary-to-text encoding scheme that represents binary data in a printable ASCII string format. Base64 is commonly used for encoding binary data in contexts where only text can be stored or transmitted, such as email attachments, URLs, and data URIs.

The crate supports multiple Base64 alphabets and configurations, including standard Base64, URL-safe Base64, and custom alphabets. The Engine trait provides encoding and decoding with configurable alphabets.

Examples

Basic encoding and decoding:

use base64::{Engine as _, engine::general_purpose::STANDARD};

let original = b"Hello, world!";
let encoded = STANDARD.encode(original);
println!("Encoded: {}", encoded); // "SGVsbG8sIHdvcmxkIQ=="

let decoded = STANDARD.decode(&encoded).unwrap();
assert_eq!(decoded, original);

Using URL-safe encoding for use in URLs:

use base64::{Engine as _, engine::general_purpose};

let data = b"data with/special+chars";
let encoded = general_purpose::URL_SAFE_NO_PAD.encode(data);
println!("URL-safe: {}", encoded); // Uses - and _ instead of + and /

let decoded = general_purpose::URL_SAFE_NO_PAD.decode(&encoded).unwrap();
assert_eq!(decoded, data);