• Select Encode or Decode mode based on your needs.
• Toggle URL-safe format if you need to use the Base64 data in URLs (uses '-' and '_' instead of '+' and '/').
• Choose between Text Input or File Input tabs.
• Enter text or upload a file, then click the Encode/Decode button.
• Copy or download the result using the provided buttons.
• All processing happens in your browser - your data is never sent to our servers.

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It uses a set of 64 different characters (hence the name) to represent binary data.

This encoding is commonly used when there is a need to encode binary data that needs to be stored and transferred over media designed to deal with text rather than binary data. Base64 encoding ensures that the data remains intact without modification during transport.

Base64 encoding works by dividing every 3 bytes (24 bits) of binary data into 4 groups of 6 bits each. Each group of 6 bits is then represented by a character from the Base64 character set.

The character set includes A-Z, a-z, 0-9, and two additional characters, typically '+' and '/' (though these can vary). If the binary data length is not a multiple of 3, padding with '=' characters is added to make the encoded output length a multiple of 4.

• Email Attachments: MIME format uses Base64 to encode binary attachments in email.
• Data URIs: Embedding images directly in HTML/CSS using the data URI scheme.
• JSON Web Tokens (JWT): Encoding claims information when transmitting authentication data.
• API Communications: Encoding binary data when passing information between different systems via text-based protocols.
• Storing Binary Data: In databases or systems that might not handle binary data well.

There are several variations of Base64 encoding designed for specific use cases:

• Base64URL: A URL and filename safe variant that replaces '+' with '-' and '/' with '_'.
• Base64 without padding: Omits the '=' padding characters for slight space savings.
• Modified Base64 for filenames: Used in systems where certain characters might cause issues with filenames.
• Radix-64: Used in OpenPGP and similar applications with a slightly different character set.

• Size Increase: Base64-encoded data is approximately 33% larger than the original binary data.
• Processing Overhead: Encoding and decoding requires additional computational resources.
• Not Encryption: Base64 is not a security measure and provides no encryption or protection of data.
• URL Safety: Standard Base64 can include characters that need to be URL-encoded when used in URLs (unless using Base64URL variant).