Bitly is a URL shortening service and a link management platform. The company Bitly, Inc. was established in 2008. It is privately held and based in New York City. Bitly shortens 600 million links per month, for use in social networking, SMS, and email. Bitly makes money by charging for access to aggregate data created as a result of many people using the shortened URLs.

In 2017, Spectrum Equity acquired a majority stake in Bitly for $63 million.

From November 2023, guest users can no longer create short links; an account is required.

The Bitly URL shortening service became popular on Twitter after it became the default URL shortening service on the website on May 6, 2009. It was subsequently replaced by Twitter's own t.co service.

The company behind Bitly launched a similar service, but for online videos, to determine what videos are the most popular on the web.

The company offers a paid solution called Bitly Enterprise that provides advanced branding features, audience intel, omnichannel campaign tracking, custom QR codes and more. Companies can use their own custom domains to generate shortened links; for example, The New York Times uses nyti.ms and Pepsi uses pep.si. This allows the company to push brand awareness on services such as Twitter but use the Bitly engine to generate the shortened URLs and track marketing metrics. Bitly Enterprise also has advanced analytics features and uses Bitly data to provide advanced social insight tools for companies and brands.

In December 2021, Bitly acquired Egoditor GmbH, developer of QR Code Generator, as part of its expansion beyond link shortening.

The company uses HTTP 301 redirects for its links. The shortcuts are intended to be permanent and cannot be changed once they are created. URLs that are shortened with the bitly service use the bit.ly domain or any other generic domain that the service offers.