Dayforce, Inc., formerly Ceridian, is an American human resources software and services company. It is a publicly traded on the New York Stock Exchange and Toronto Stock Exchange.

Dayforce is also the name of the company's cloud Human Capital Management (HCM) platform, which covers the full suite of human capital management software, including payroll, tax filing, benefits, HR, talent intelligence, workforce management, and recruiting technology.

Dayforce, formerly Ceridian, is a descendant of Control Data Corporation (CDC). In 1992, Ceridian Corporation was founded as an information services company from the restructuring of CDC, a computer services and manufacturing company founded in 1957. The computer product business was spun-off as Control Data Systems (CDS) and took the Control Data name.

In March 2001, Ceridian was split into two independent companies, with the "old" Ceridian Corporation changed its name to Arbitron and the rest of company (consisting of human resources services and Comdata business) took the Ceridian name.

In 2007, Ceridian was acquired for US$5.3 billion by Thomas H. Lee Partners and Fidelity National Financial (FNF). Ceridian common stock ceased trading on the NYSE before commencement of trading on November 9, 2007 and was delisted from the NYSE.

In March 2012, Ceridian completed its acquisition of Dayforce, a single SaaS application for HR, payroll, tax, benefits, workforce management, talent management, and several related activities. In October 2013, Ceridian announced the legal separation of its Human Capital Management and payments businesses. Ceridian completed the separation on October 1, 2013 through a series of transactions, which resulted in the payments business being operated as Comdata Inc. (“Comdata”), and the HCM business being operated as Ceridian HCM Holding Inc. (“Ceridian HCM”).

In April 2018, Ceridian went public in an initial offering that raised over $400 million.

In September 2019, Ceridian acquired Australia-based enterprise HR software company Riteq.