System1
| Type | Public |
|---|---|
| NYSE: SST | |
| Industry | News media security Internet advertising |
| Founded | 2013 |
| Headquarters | United States  |
| Key people | Michael Blend (Co-founder/CEO) Chuck Ursini (Co-founder/COO) Brian Coppola (CPO) |
| Products | Answers.com, HowStuffWorks, Info.com, Infospace, MapQuest, Startpage.com, Formerly: Waterfox |
| Revenue |  US$266 million (2025) |
 −US$65.3 million (2025) | |
| Website | system1 |
System1 is an American Internet advertising company. Formerly known as OpenMail, it was founded in 2013. It describes itself as operating a "Responsive Acquisition Marketing Platform", and cites privacy as one of its principal foci, although it has been criticized for its influence on privacy-focused properties, including search engine Startpage.com. It is headquartered in Marina del Rey, California.