Base64 Encoder
Encode and decode Base64 strings instantly.
Encoding and decoding happen entirely in your browser using the standard Base64 algorithm — nothing is sent to a server.
What Base64 is actually used forUse cases
Base64 is a way of representing binary or text data using only 64 printable characters (A–Z, a–z, 0–9, + and /), which makes it safe to embed inside places that only expect plain text — JSON payloads, URLs, email attachments, or CSS/HTML files. Developers commonly hit it when inspecting API authentication headers, debugging JWT tokens (the middle section of a JWT is Base64-encoded JSON), or embedding a small image directly inside a CSS file as a data URI.
This tool encodes and decodes using the browser’s native btoa() and atob() functions, with additional handling so that special characters and emoji (UTF-8 text) encode and decode correctly — a common gap in simpler Base64 tools that only handle plain ASCII.
Base64 Encoder — FAQ
What is Base64 encoding actually used for?
It’s commonly used to safely embed binary or special-character data inside text-based formats — email attachments, image data URIs in CSS, API tokens, and parts of JWT authentication tokens.
Why do I get an error when decoding?
Base64 decoding fails when the text you paste isn’t valid Base64 — for example, if it contains characters outside the standard Base64 set, or if the string’s length isn’t padded correctly. Double check you copied the entire encoded string.
Does this work with images, or only text?
This tool is built for text input and output. It correctly encodes and decodes UTF-8 text, including accented characters and emoji, but it doesn’t accept direct image file uploads.
Is Base64 the same thing as encryption?
No. Base64 is an encoding scheme, not encryption — anyone can decode it back to the original text instantly. It doesn’t provide any security or confidentiality; it just changes the format the data is represented in.