Base64 is a way of representing binary data using only 64 readable ASCII characters. It is everywhere in modern computing — from embedding images directly in web pages to encoding credentials in API requests — yet it is often misunderstood.
What problem does Base64 solve?
Many systems were designed to handle plain text rather than raw binary. Base64 converts any data into a safe, text-only form that can travel through email, URLs, JSON and HTML without being corrupted. It is not encryption: anyone can decode it, so it should never be used to hide secrets.
How Base64 works
The encoder takes three bytes of input (24 bits) and splits them into four 6-bit groups, each mapped to one of 64 characters (A–Z, a–z, 0–9, + and /). When the input length is not a multiple of three, padding characters (=) keep the output aligned.
Common uses
Developers use Base64 to embed small images as data URIs, to encode binary attachments, to store tokens, and to transmit data through channels that only accept text. Knowing how to quickly encode and decode it is a useful everyday skill.
Encode and decode online, privately
With a browser-based Base64 tool you paste your text or encoded string, choose encode or decode, and get the result instantly. Because everything runs locally, sensitive values never leave your device.