Home
Developer Tool

Base64 Encoder / Decoder

Encode or decode text and files to Base64 instantly in your browser. Supports UTF-8 and URL-safe mode.

Text to encode
Base64
Encode a file to Base64
Drop a file or click to browse
Images, PDFs, binaries… any format accepted

What is Base64?

How it works

Base64 converts binary data to ASCII text using 64 printable characters. Every 3 bytes become 4 characters, adding ~33% overhead.

Web use cases

Embedding images in CSS (data URLs), MIME email attachments, sending binary data through JSON APIs without corruption.

URL-safe Base64

URL-safe variant replaces + with - and / with _ for safe use in URLs and JWT tokens without percent-encoding.

File encoding

Convert any binary file (image, PDF, font…) into a Base64 string to embed it directly into HTML, CSS, or JSON without external requests.

FAQ

Is Base64 a form of encryption?
No. Base64 is an encoding scheme, not encryption. Anyone can decode Base64 without a key. Never use it to hide sensitive data.
Why does Base64 increase the size by ~33%?
3 bytes (24 bits) of binary data are represented as 4 Base64 characters (each encoding 6 bits). The 4/3 ratio gives roughly 33% overhead.
What is the difference between standard and URL-safe Base64?
Standard Base64 uses + and / which have special meaning in URLs. URL-safe replaces them with - and _ so the output can be used directly in URLs and JWT tokens.
Is my data processed on your servers?
No. All encoding and decoding happens 100% in your browser using native JavaScript APIs. Nothing is ever sent to a server.