Base64 Encoder / Decoder

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It's commonly used to embed data in text-based formats like HTML, CSS, or JSON, or to transmit data over channels that only support text. Base64 is essential for web functionality, enabling everything from embedding images directly in stylesheets to sending attachments in emails. This tool provides a simple, secure, and instant way to work with Base64 encoding. Because it operates entirely within your browser, your data is never sent to a server, guaranteeing its privacy. This makes it safe to use for any type of data, including sensitive API keys or other credentials that should not be exposed.

How to Use This Tool:

• To Encode: Type or paste your text into the input field and click "Encode". The tool will convert your text into a Base64 string. Our tool correctly handles Unicode and UTF-8 characters, so you can encode text from any language.
• To Decode: Paste a Base64 string into the input field and click "Decode". The tool will convert it back to the original text. If the string is not a valid Base64 string, it will display an error.

Important: Base64 is an encoding method, not encryption. It provides no security and can be easily reversed. Do not use it to protect sensitive information. For that, you need to use proper cryptographic algorithms.

Technical Deep Dive

The Base64 encoding process is a clever bit of data manipulation designed for compatibility. At its core, it takes a stream of binary data and translates it into a limited set of 64 common ASCII characters that are safe to transmit over any text-based system. The standard character set includes A-Z, a-z, 0-9, and the '+' and '/' symbols. The '=' character is also used for padding.

The process works by taking 3 bytes (a total of 24 bits) of the input data at a time. This 24-bit block is then divided into four 6-bit chunks. Since 2^6 equals 64, each 6-bit chunk can be represented by one of the 64 characters in the Base64 alphabet. For example, the binary sequence `000000` maps to 'A', `000001` maps to 'B', and so on. This continues until all the input data has been processed. If the final block of input data is less than 3 bytes long, padding is added. If there's one byte left, it's treated as 8 bits, and two padding characters ('==') are added to the output. If two bytes are left, they are treated as 16 bits, and one padding character ('=') is added. This ensures the output string's length is always a multiple of 4.

This conversion from 3 bytes to 4 characters is why Base64-encoded data is approximately 33% larger than the original binary data. It's a necessary trade-off to guarantee that the data can pass through any system without being corrupted. When decoding, the process is simply reversed: each Base64 character is converted back to its 6-bit value, these are concatenated back into 24-bit chunks, and those are then re-formed into their original 3-byte sequence. Our tool also correctly handles modern text by first encoding the input string to UTF-8 bytes before the Base64 conversion, ensuring that international characters and emojis are preserved perfectly.