HTTPS Everywhere is a discontinued free and open-source browser extension for Google Chrome, Microsoft Edge, Mozilla Firefox, Opera, Brave, Vivaldi and Firefox for Android, which was developed collaboratively by The Tor Project and the Electronic Frontier Foundation (EFF).

[5] The option "Encrypt All Sites Eligible" makes it possible to block and unblock all non-HTTPS browser connections with one click.

[6] Due to the widespread adoption of HTTPS on the World Wide Web, and the integration of HTTPS-only mode on major browsers, the extension was retired in January 2023.

[9] The code, in part, is based on NoScript's HTTP Strict Transport Security implementation, but HTTPS Everywhere is intended to be simpler to use than No Script's forced HTTPS functionality which requires the user to manually add websites to a list.

The SSAC criticized SSL Observatory for potentially significantly undercounting internal name certificates, and noted that it used a data set from 2010.