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BASE64/RADIX64 Coder

This page uses JavaScript to decode/encode BASE64 strings. Enter the string in the space below.

Use this button for decoding the headers of PGP sigs and keys:

What is BASE64?

A method of encoding binary data within text. If you'll remember, binary data is a full 8-bits per byte, whereas text uses a little more than 6 bits per byte. A 6-bit number has 64 combinations, hence the term "BASE64".

The way it works is that every three 8-bit bytes are stored in four 6-bit characters, where the characters are in the range [A-Z][a-z][0-9][+/]. (Count 'em up; that's 64 total characters). Since this doesn't exactly line up, pad characters of [=] are used at the very end.

Where BASE64 is used

HTTP "Basic" Authentication
PGP signatures and keys
One of many ways of encoding e-mail

I wrote this little decoder because I'm regularly confronted with little strings I want to decode. Note that the PGP decode routines are far from complete. I will likely only update them as I encouter PGP data that I want to decode further.

Documentation

Some documentation on Base64 (aka. Radix64) encoding can be found in the OpenPGP RFC 2440. I've also created a brief PGP decoder based upon that RFC.

JavaScript

Of course, if you are like me, you turned off JavaScript a long time ago because it's a huge security risk. This is why Internet Explorer is my primary browser: I've got everything turned off. When I need to use JavaScript, I switched to Netscape.