Also, according to Wikipedia, base64 encoding makes the file size 33% larger than the binary file, and compressing it (as with gzip) only shaves off 2-3% of the

Also, according to Wikipedia, base64 encoding makes the file size 33% larger than the binary file, and compressing it (as with gzip) only shaves off 2-3% of the base64 file size. Nope, the second part is wrong. See also the discussion here http://news.ycombinator.com/item?id=1491165 http://news.ycombinator.com/item?id=1491165 - overhead of compressed base64 tends to be very small, smaller than the HTTP protocol overhead. Base64 has only 6 bits of entropy and Huffman coding is able to take advantage of this.