Base64 Encoder/Decoder
Encode and decode Base64 data online. Supports text and file encoding with full Unicode/CJK character support.
What is Base64?
Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters. It is commonly used to embed images, files, and other binary data in text-based formats such as JSON, XML, HTML, and email attachments.
To encode text or files, paste your content into the input field or upload a file, then click Encode. For decoding, paste the Base64 string and click Decode. Toggle URL-safe mode when the encoded output will appear in URLs or filenames.
Developers frequently use Base64 to embed small images as data URIs in HTML and CSS, transmit binary data through REST APIs that only support text, and encode email attachments via MIME. It is also used to store binary blobs in JSON configuration files and database text columns.
Base64 works by grouping every three bytes of input into four 6-bit values, each mapped to a character from A-Z, a-z, 0-9, +, and /. This process increases the data size by roughly 33%. The padding character '=' is appended when the input length is not a multiple of three.