Deque Systems (/ˈdiːkjuː/ DEE-kew) is a digital accessibility company based in Herndon, Virginia with additional offices in Kavuri Hills Madhapur, Hyderabad India and Utrecht, The Netherlands.

[citation needed] In June, 2015 Deque open-sourced the accessibility rules engine axe-core.

[3] In September 2020, Deque found that the majority of vote by mail applications were inaccessible, and fixed them for the 2020 Presidential Election.

[4][5][6][7] Deque tools, services and training are used to achieve compliance in support of the W3C's Web Content Accessibility Guidelines,[8] the Americans with Disabilities Act, Section 508 and EN 301 549.

[10] axe is a suite of accessibility testing tools for HTML, Android, and iOS applications.