Check if twitter username exists

Question

Is there a way to check if a twitter username exists? Without being authenticated with OAuth or the twitter basic authentication?

Answer 1

As of right now, you're better off using the API the signup form uses to check username availability in realtime. Requests are of the format:

https://twitter.com/users/username_available?username=whatever

And give you a JSON response with a valid key giving you a true if the username can be registered:

{"valid":false,"reason":"taken","msg":"Username has already been taken","desc":"That username has been taken. Please choose another."}
{"valid":true,"reason":"available","msg":"Available!","desc":"Available!"}
{"valid":false,"reason":"is_banned_word","msg":"Username is unavailable","desc":"The username \"root\" is unavailable. Sorry!"}

The reason this is better than checking for 404 responses is that sometimes words are reserved (like 'root' above), or a username is actually taken but for some reason the account is gone from the Twitter front end.