ADP

ADP, or Automatic Data Processing, is one of the largest and oldest payroll and human capital management companies in the world. It processes payroll for roughly one in six American workers, making it the backbone of payroll infrastructure for businesses of every size. For custom web application development, ADP's APIs and integration marketplace allow developers to connect custom systems with payroll data, employee records, time and attendance information, and benefits enrollment. When building enterprise applications, ADP integration is often a requirement because the client's payroll already runs through ADP and they need the new system to work with their existing data rather than duplicating it.

ADP was founded in 1949 by Henry Taub in Paterson, New Jersey, making it one of the oldest technology companies in continuous operation. Taub was just 22 years old when he started the business with a $3,000 investment from his father. The original company name was Automatic Payrolls, Inc., and it literally processed payroll by hand for small businesses using adding machines and ledger books. The company automated its processes over the decades as computing technology advanced, transitioning from manual bookkeeping to mainframe computers to cloud-based systems. ADP went public in 1961 and has been on the Fortune 500 list for decades.

ADP's payroll data has become so comprehensive that the company publishes the ADP National Employment Report, a monthly estimate of U.S. private-sector employment that financial markets and economists watch closely. The report, produced in collaboration with Moody's Analytics, is based on the actual payroll data of roughly 26 million employees processed through ADP's systems. It is released two days before the official Bureau of Labor Statistics employment report and is considered one of the most reliable leading indicators of the government's jobs numbers. Wall Street traders routinely adjust their positions based on ADP's report, giving a payroll company outsized influence on financial markets.