Base64 Encoder/Decoder Online - EXUtil Extended Utilities

Free online Base64 encoder and decoder. Convert text to Base64 and back with one click. Supports file import for batch processing of encoded data.

How to use

  1. Paste or import the content you want to process.
  2. Choose an available action and run the tool.
  3. Review the result, then copy or download the output.

Frequently asked questions

Is Base64 encryption?
No, Base64 is not encryption, just an encoding method. It converts binary data to printable ASCII characters that anyone can decode. Use encryption tools if you need encryption.
How to tell if a string is Base64?
Base64 strings only contain A-Z, a-z, 0-9, +, / and = padding characters, and the length is usually a multiple of 4. If it contains other characters, it's not standard Base64.
How much does Base64 increase size?
Base64 encoding increases data size by approximately 33%. Every 3 bytes of binary data are encoded as 4 Base64 characters.
What's the difference between Base64 and Base64URL?
Base64URL is a variant of Base64 that replaces + with - and / with _, and removes padding =, making it suitable for use in URLs.
Why does decoding fail?
Common reasons include: 1) Input is not valid Base64; 2) Contains illegal characters; 3) Incorrect padding position; 4) Data was corrupted during transmission.

References

Technical standards and official documentation related to this tool.