You can use btoa()
and atob()
to convert to and from base64 encoding.
There appears to be some confusion in the comments regarding what these functions accept/return, so…
btoa()
accepts a “string” where each character represents an 8-bit byte – if you pass a string containing characters that can’t be represented in 8 bits, it will probably break. This isn’t a problem if you’re actually treating the string as a byte array, but if you’re trying to do something else then you’ll have to encode it first.atob()
returns a “string” where each character represents an 8-bit byte – that is, its value will be between0
and0xff
. This does not mean it’s ASCII – presumably if you’re using this function at all, you expect to be working with binary data and not text.
See also:
- How do I load binary image data using Javascript and XMLHttpRequest?
Most comments here are outdated. You can probably use both btoa()
and atob()
, unless you support really outdated browsers.