Twitter automatically shortens URLs posted on their social networking platform. So that you don’t need to use external link shorteners like Bitly unless you’re looking for data analytics like how many people have clicked your link.
Twitter & T.co
Twitter is limited to less than 280 characters for tweets. Users used to rely on link shortener websites to shrink URLs before posting to Twitter. These link shorteners made sure URLs didn’t take up a lot of space in a tweet. To minimize the number of characters, Twitter introduced its own link shorter – t.co.
Once you enter a URL in the Twitter tweet area, it is updated to 23 characters by the t.co service, irrespective of the original URL length. If the URL is less than 23, it still counts as 23 characters. You can not opt-out of the t.co link shortening, since Twitter uses it to collect information about how often a post is clicked. Twitter also protects users from a list of potentially dangerous websites by testing their converted links with their t.co service. If a site is harmful, users will see a warning before it can proceed.
Using Twitter URL Shortener (Like Bitly).
Bitly and a few more websites that reduce URLs differ from other sites that reduce links by offering information on shortened links. For example, when you use Bitly, you enter a URL and click on Shorten to get a short link of fewer than 23 characters. This link can be used on Twitter, but the t.co service still counts it as 23 characters.
Twitter has no advantage in using links that are shortened by other services. All of them have the same length. The only justification for accessing a connection shortener is to use the details on the shortened URL. This information is received about the number of clicks of a shortened link, users’ location using the link and the reference websites, but you still have to create an account to access them.