Base64 Decoder & Encoder
beginnerEncodes binary data using 64 printable ASCII characters
What is Base64?
Base64 is an encoding scheme that converts binary data into a text string using 64 printable ASCII characters (A-Z, a-z, 0-9, + and /). It's not a cipher — it provides no security — but is widely used to safely transmit binary data over text-based systems.
How Base64 Works
The encoder takes 3 bytes (24 bits) of input data at a time and converts them into 4 Base64 characters. Each Base64 character represents 6 bits. If the input length isn't divisible by 3, = padding characters are added.
Base64 in Pop Culture
Base64 appears in web development constantly — email attachments, data URIs (images embedded in CSS), JSON web tokens (JWT), and API authentication headers all commonly use Base64 encoding.
How to Break Base64
Base64 needs no "breaking" — it's a public encoding with no secret key. Paste it into our decoder to get the original text.
Frequently Asked Questions
How do I decode Base64?
Enter your ciphertext in the tool above, select "Base64" from the dropdown, choose Decode mode, and click the button. Results appear instantly.
What is Base64 used for?
Base64 was used for secret communication. While not secure by modern standards, it's widely used in puzzles, escape rooms, and educational contexts.
How secure is Base64?
Base64 is not secure by modern standards — it can be broken quickly with basic cryptanalysis or brute force. Use it for puzzles and learning, not sensitive data.