Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 strings back to readable text. Supports UTF-8 and Unicode characters.
Free Online Base64 Encoder & Decoder
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It's widely used in email attachments (MIME), data URLs in HTML/CSS, JWT tokens, API authentication headers, and storing binary data in text-based formats like JSON and XML.
How Base64 Encoding Works
Base64 takes every 3 bytes of input and converts them into 4 ASCII characters from a set of 64 characters (A-Z, a-z, 0-9, +, /). This means Base64-encoded data is always about 33% larger than the original. The padding character "=" is added at the end when the input length isn't divisible by 3.
Common Use Cases
Embedding images directly in HTML or CSS using data URIs. Encoding API keys and credentials for HTTP Basic Authentication headers. Transmitting binary data through text-only channels like email (MIME encoding). Storing binary blobs in JSON or XML documents. Working with JWT (JSON Web Token) payloads in web authentication.
Frequently Asked Questions
No. Base64 is encoding, not encryption. It doesn't provide any security — anyone can decode Base64 text. It's meant for data representation, not data protection.
Base64 uses 4 characters to represent every 3 bytes of input. This 4:3 ratio means the encoded output is approximately 33% larger than the original data. The trade-off is compatibility — Base64 text can safely pass through any text-based system.
Yes. This tool uses UTF-8 encoding before Base64 conversion, so it correctly handles all Unicode characters including accented letters, CJK characters, and emojis.