Base64 Encode / Decode

Base64 is a way to represent binary data using only ASCII text characters (A-Z, a-z, 0-9, +, /). It's used when binary data needs to be stored or transmitted in text-only formats.

Base64url is a URL-safe variant that uses - and _ instead of + and / and omits padding (=). It's used in JWTs and URLs where standard Base64 characters would cause problems.

Base64 encoding increases data size by approximately 33% because it represents 3 bytes of binary data using 4 ASCII characters. This is the tradeoff for text-safe encoding.

Yes, but browser memory limits apply. Files up to ~50MB should work fine in most modern browsers. For very large files, consider using server-side tools or command-line utilities.