Sendbird developed a messaging-as-a-service application programming interface (API) that provides chat, voice and video messaging for mobile apps and websites. The company was founded in 2013 by Brandon Y Jeon, Forest Lee, Harry Kim, and John S. Kim and is headquartered in San Mateo, California, United States. Since hatching out of the Y Combinator in 2016, Sendbird's platform has grown to serve over 300M monthly chat users across companies including DoorDash, PayPal, Yahoo!, Rakuten, and Walgreens. Sendbird officially became a Unicorn in 2021.