Tinder is an online dating and geosocial networking application. In Tinder, users "swipe right" to like or "swipe left" to dislike other users' profiles, which include their photos, a short bio, and a list of their interests. Tinder uses a "double opt-in" system where both users must like each other before they can exchange messages. Tinder was launched by Sean Rad at a hackathon held at the Hatch Labs incubator in West Hollywood in 2012. By 2014, Tinder was registering about one billion daily "swipes" and reported that users logged into the app on average 11 times a day. In 2015, Tinder was the fifth highest-grossing mobile app,  and by 2019 it was the highest-grossing app. In 2020, Tinder had 6.2 million subscribers and 75 million monthly active users.  As of 2021, Tinder has recorded more than 65 billion matches worldwide. The original prototype for Tinder, called 'MatchBox', was built during a hackathon in February 2012 by Sean Rad and engineer Joe Munoz. The hackathon was hosted by Hatch Labs, a NY-based startup incubator with a West Hollywood outpost. Realizing the name MatchBox was too similar to Match.com, Rad, his co-founders, and early employees renamed the company Tinder. The company's flame-themed logo remained consistent throughout the rebranding. The original prototype for Tinder, called 'MatchBox', was built during a hackathon in February 2012 by Sean Rad and engineer Joe Munoz. The hackathon was hosted by Hatch Labs, a NY-based startup incubator with a West Hollywood outpost. Realizing the name MatchBox was too similar to Match.com, Rad, his co-founders, and early employees renamed the company Tinder. The company's flame-themed logo remained consistent throughout the rebranding.

In January 2012, Rad was hired as General Manager of Cardify, a credit card loyalty app launched by Hatch Labs. During a hackathon in his first month, he presented the idea for a dating app called Matchbox. Rad and engineer Joe Munoz built the prototype for MatchBox and presented the "double opt-in" dating app on February 16, 2012.

In March, co-founder Jonathan Badeen (front-end operator and later Tinder's CSO), and Chris Gulczynski (designer and later Tinder's CCO) joined Cardify.

In May, while Cardify was going through Apple's App Store approval process, the team focused on MatchBox. During the same period, Alexa Mateen (Justin's sister) and her friend, Whitney Wolfe Herd, were hired as Cardify sales reps.

In August 2012, Cardify was abandoned, Matchbox was renamed Tinder, and co-founder Justin Mateen (marketer and later Tinder's CMO) joined the company.

In September 2012, Tinder was soft-launched in the App Store. It was then launched at several college campuses and started to expand quickly.