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Base64 Encoder/Decoder

Encode and decode Base64 with variants

Base64 Encoder/Decoder

Professional Base64 encoding and decoding tool with support for multiple variants including URL-safe, Base32, and Base16

Input

Enter text to encode using Standard Base64

ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/

Output

Encoded result

Quick Examples

Click any example to try it

Hello World!
SGVsbG8gV29ybGQh
CTF{example_flag}
Q1RGe2V4YW1wbGVfZmxhZ30=
admin:password
YWRtaW46cGFzc3dvcmQ=
flag{base64_is_easy}
ZmxhZ3tiYXNlNjRfaXNfZWFzeX0=
The quick brown fox
VGhlIHF1aWNrIGJyb3duIGZveA==
{"user":"admin"}
eyJ1c2VyIjoiYWRtaW4ifQ==

CTF Tips for Base64

  • • Base64 strings often end with = or == padding characters
  • • Look for Base64 in URLs, cookies, and HTTP headers
  • • Try URL-safe variant if standard Base64 fails
  • • Base64 can be nested - decode multiple times
  • • Check for Base32/Base16 if Base64 doesn't work
  • • Some CTFs use custom Base64 alphabets