I needed this for a project and decided to put it here for future use.
If you are using the Google JSAPI loader, this is useful for encoding the JSAPI url. Just paste the part the url portion after the “autoload=” portion, and encode it here. Or, decode it again so you can figure out what the heck is it.
This is often useful for encoding your User Agent string, which you can quickly find here (copy it, paste it here) – Whatismyuseragent.com