Remove trailing “=” when base64 encoding

Question

I am noticing that whenever I base64 encode a string, a \"=\" is appended at the end. Can I remove this character and then reliably decode it later by adding it back, or is

Answer 1

I wrote part of Apache's commons-codec-1.4.jar Base64 decoder, and in that logic we are fine without padding characters. End-of-file and End-of-stream are just as good indicators that the Base64 message is finished as any number of '=' characters!

The URL-Safe variant we introduced in commons-codec-1.4 omits the padding characters on purpose to keep things smaller!

http://commons.apache.org/codec/apidocs/src-html/org/apache/commons/codec/binary/Base64.html#line.478

I guess a safer answer is, "depends on your decoder implementation," but logically it is not hard to write a decoder that doesn't need padding.