Base64 Encoder/Decoder
Encode text to Base64 or decode Base64 strings instantly. Full UTF-8 support. Free online Base64 tool — runs in your browser, no data uploaded.
About this tool
Base64 is a binary-to-text encoding scheme that represents binary data as printable ASCII characters. It is widely used in email attachments (MIME), data URIs in HTML/CSS, JSON Web Tokens (JWT), and API communication where binary data must travel through text-only channels.
This encoder and decoder fully supports UTF-8, which means international characters, emojis, and special symbols are handled correctly. All processing happens entirely in your browser -- nothing is sent to a server, keeping your data private.
infoHow It Works
Each group of 3 bytes is split into four 6-bit numbers, each mapped to a printable ASCII character (A-Z, a-z, 0-9, +, /).
If the input length is not a multiple of 3, one or two "=" characters are appended to the output.
Base64 output is roughly 33% larger than the original data because 3 bytes become 4 characters.
lightbulbTip
Base64 is an encoding, not encryption. It does not provide any security. Never use it to hide sensitive data -- anyone can decode it.
Frequently Asked Questions
What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It's commonly used to embed images in HTML/CSS, transmit data in URLs, and encode email attachments.
Does this tool support Unicode/UTF-8?
Yes. The encoder properly handles UTF-8 characters including emojis, accented characters, and non-Latin scripts. It uses encodeURIComponent for safe Unicode encoding.
Is my data safe when using this tool?
Yes. All encoding and decoding happens entirely in your browser. No data is sent to any server. This tool is safe for encoding sensitive information like API keys or tokens.