Base64 Encoder/Decoder

Base64 is a binary-to-text encoding scheme that converts binary data into a string of ASCII characters. It uses a set of 64 characters (A-Z, a-z, 0-9, +, and /) to represent data, with = used for padding. Base64 is commonly used to embed images in HTML or CSS via data URLs, transmit binary attachments in email (MIME), and include binary data in JSON or XML payloads. It increases the data size by roughly 33%, so it is best used when you need text-safe representation rather than compact storage.

Select Encode mode to convert plain text into Base64, or Decode mode to convert a Base64 string back to readable text. The conversion happens in real time as you type, so there is no need to click a button. The tool fully supports UTF-8 characters, including emoji, accented characters, and CJK scripts. Use the Copy Output button to quickly grab the result for pasting into your code, API request, or configuration file. All processing runs entirely in your browser with no server calls.

Developers frequently use Base64 when embedding small images directly in CSS or HTML to reduce HTTP requests. It is also essential for encoding authentication credentials in HTTP Basic Auth headers, where the username and password are combined and Base64-encoded. API developers use it to send binary file contents in JSON request bodies. Keep in mind that Base64 is encoding, not encryption. Anyone can decode a Base64 string, so never use it as a security measure for sensitive data. If you also need to encode special characters for URLs, check out our URL Encoder/Decoder. For verifying data integrity, our Hash Generator can produce SHA-256 and other cryptographic hashes.