Formulus® System Requirements

To ensure the best Formulus experience, and to conform with the most recent Internet security standards, use this recommended web browser technology.
(Updated March 2020)


OS/Browser Recommendations

  • Windows 10: Firefox 65 and higher, Firefox 60 (ESR); Internet Explorer 11; Chrome 63 and higher
  • Windows 8.1: Firefox 65 and higher, Firefox 60 (ESR); Internet Explorer 11; Chrome 63 and higher
  • Mac OS 10.12 and higher: Safari 11 and higher; Firefox 65 and higher, Firefox 60 (ESR); Chrome 63 and higher

Internet Connection Requirements

Check with your organization's Site Administrator, Key Contact or help desk before changing any settings to conform to these requirements.

  • SSL (https) connection to formulus.cas.org.

Additional Recommendations and Requirements

  • JavaScript, cookies, and browser local storage must be enabled
  • Add https://formulus.cas.org to your browser’s "Trusted Sites" and Pop-up blocker Exceptions lists
  • A PDF reader is required for printing Formulus answers and other information. Adobe Reader can be used with Mac or Windows computers.
    Preview is a free viewer provided with Mac OS X.
  • Appropriate ActiveX and plug-in permissions are required for Internet Explorer.