On what date did Google Gmail launch as an invitation-only email service?

Google Gmail launched as an invitation-only email service on April 1, 2004.

Its release date was also April Fools’ Day, which led many people to initially suspect that Gmail was a joke. Google made the service distinctive by offering 1 gigabyte of storage, far more than many competing webmail services provided at the time.

Gmail invitations were initially limited, and users commonly received access through existing account holders. The service later expanded availability and became one of Google’s most widely used consumer products.

Gmail is sometimes confused with Google Mail, the name used in some countries because of trademark issues. Its launch also preceded Google’s later workplace branding, including Google Apps and Google Workspace.