Base64 Encoder & Decoder

Encode text and files to Base64, or decode Base64 strings back to plain text. Operates entirely in your browser with support for UTF-8 characters and URL-safe Base64 formatting without relying on external servers.

Base64 is a standard binary-to-text encoding scheme. It is designed to take raw binary data and translate it into a readable string of ASCII characters. This is essential when you need to transfer data over protocols that are designed to handle only text, such as embedding image data directly into CSS files, sending attachments via SMTP email protocols, or passing complex binary configurations inside JSON payloads. Note that Base64 encoding generally increases the representation size of the data by approximately 33%.

This tool uses native browser APIs (`btoa` and `atob`) to convert your input. However, native browser Base64 functions struggle with modern Unicode strings containing emojis or non-Latin characters. For text encoding, this tool safely handles UTF-8 characters by applying `encodeURIComponent` and `decodeURIComponent` before converting to Base64, ensuring special characters are preserved without throwing invalid character errors.

For files (like images, PDFs, or documents), the converter uses the browser's native `FileReader` API to generate a standard Base64 Data URL directly on your device. Furthermore, standard Base64 includes `+` and `/` characters, which can break URLs or file systems. By enabling the URL-Safe option, the encoder modifies the alphabet, replacing `+` with `-` and `/` with `_`, and stripping the `=` padding from the end of the string, making the result entirely safe for web transmission.

A common misconception is that Base64 protects data. Base64 is merely an encoding method; it is absolutely not an encryption method and provides zero cryptographic security. Anyone who intercepts a Base64 string can easily decode it back to its original format instantly. Encoded data should never be treated as secret or secure without a secondary layer of actual encryption.