Schmidt is an active member of the Berggruen Institute's 21st Century Council, and its board of Directors.

Schmidt graduated from Yorktown High School in the Yorktown neighborhood of Arlington County, Virginia, in 1972, after earning eight varsity letter awards in long-distance running. He attended Princeton University, starting as an architecture major and switching to electrical engineering, earning a B.S. degree in 1976. From 1976 to 1980, Schmidt stayed at the International House Berkeley, where he met his Future wife, Wendy Boyle. In 1979, at the University of California, Berkeley, Schmidt then earned an M.S. degree for designing and implementing a network (Berknet) linking the campus computer center with the CS and EECS departments. There, he also earned a Ph.D. degree in 1982 in EECS, with a dissertation about the problems of managing distributed software development and tools for solving these problems.

In June 1980, Schmidt married Wendy Susan Boyle (born in Short Hills, New Jersey, in 1955). They lived in Atherton, California, in the 1990s. They have a daughter, Sophie, and had another, Alison, who died in 2017. The two separated in 2011.

In 1983, Schmidt joined Sun Microsystems as its first software manager. He rose to become Director of software engineering, vice President and general manager of the software products division, vice President of the general systems group, and President of Sun Technology Enterprises.

Dating back to early 1990s and dubbed "Schmidt's Law" by George Gilder when Schmidt predicted that the network will become the computer. Schmidt's Law states: "When the network becomes as fast as the backplane of your computer, the computer hollows out, its components dispersing across the Web, its value migrating to search and sort functions."

In April 1997, Schmidt became the CEO and chairman of the board of Novell. He presided over a period of decline at Novell where its IPX protocol was being replaced by open TCP/IP products, while at the same time Microsoft was shipping free TCP/IP stacks in Windows 95, making Novell much less profitable. In 2001, he departed after the acquisition of Cambridge Technology Partners.

New America is a non-profit public-policy institute and think tank, founded in 1999. Schmidt succeeded founding chairman James Fallows in 2008.

Schmidt sat on the boards of trustees of Carnegie Mellon University and Princeton University. He taught at Stanford Graduate School of Business in the 2000s. Schmidt serves on the boards of the Institute for Advanced Study in Princeton, the Khan Academy, and The Economist.

In March 2001, Schmidt joined Google's board of Directors as chairman, and became the company's CEO in August 2001. At Google, Schmidt shared responsibility for Google's daily operations with founders Page and Brin. Prior to the Google initial public offering, Schmidt had responsibilities typically assigned to the CEO of a public company and focused on the management of the vice Presidents and the sales organization. According to Google, Schmidt's job responsibilities included "building the corporate infrastructure needed to maintain Google's rapid growth as a company and on ensuring that quality remains high while the product development cycle times are kept to a minimum."

In 2004, Schmidt and the Google founders agreed to a base salary of US $1 (which continued through 2010) with other compensation of $557,465 in 2006, $508,763 in 2008, and $243,661 in 2009. He did not receive any additional stock or options in 2009 or 2010. Most of his compensation was for "personal security" and charters of private aircraft.

In 2005, Google blacklisted CNET reporters from talking to Google employees for one year, until July 2006, after CNET published personal information on Schmidt, including his political donations, hobbies, salary, and neighborhood, that had been obtained through Google searches.

The Schmidt Family Foundation was established in 2006 by Wendy Schmidt and Eric Schmidt to address issues of sustainability and the responsible use of natural resources.

He is a member of the Bilderberg Group and has attended the annual Bilderberg conferences every year since 2007 (except for 2009). He also has a listed membership with the Trilateral Commission. He is a member of the International Advisory Board at the Blavatnik School of Government, University of Oxford.

Schmidt was on the list of ARTnews's 200 top art Collectors in 2008.

During an interview aired on December 3, 2009, on the CNBC documentary "Inside the Mind of Google," Schmidt was asked, "People are treating Google like their most trusted friend. Should they be?" He replied: "I think judgment matters. If you have something that you don't want anyone to know, maybe you shouldn't be doing it in the first place. But if you really need that kind of privacy, the reality is that search engines, including Google, do retain this information for some time. And it's important, for Example, that we are all subject in the United States to the Patriot Act. It is possible that information could be made available to the authorities."

In August 2010, Schmidt clarified his company's views on network neutrality: "I want to be clear what we mean by Net neutrality: What we mean is if you have one data type like video, you don't discriminate against one person's video in favor of another. But it's okay to discriminate across different types. So you could prioritize voice over video. And there is general agreement with Verizon and Google on that issue."

The Schmidt Family Foundation's subsidiaries include ReMain Nantucket and the Marine Science and Technology Foundation; its main charitable program is the 11th Hour Project. The foundation has also awarded grants to the Natural Resources Defense Council and the Energy Foundation.

In January 2013, Schmidt visited North Korea with his daughter Sophie, Jared Cohen, and former New Mexico governor bill Richardson.

In 2014, he had a cameo appearance in the film Dumb and Dumber To, starring Jim Carrey and Jeff Daniels. He also had a cameo appearance in the HBO show Silicon Valley.

In 2015, the UK Government introduced a new law intended to penalise Google and other large multinational corporations' artificial tax avoidance. Google is accused of avoiding paying tens of billions of dollars of tax through a convoluted scheme of inter-company licensing agreements and transfers to tax havens. Schmidt was also criticised for his inaccurate use of the term 'capitalism' to describe billions of dollars being transferred into tax havens where no economic activity was actually taking place.

Schmidt is an investor in Timshel, another start up company associated with Hillary Clinton's 2016 presidential campaign. Timshel is the parent company of The Groundwork.

On December 21, 2017, Schmidt announced he would be stepping down as the executive chairman of Alphabet.

Early in his career, Schmidt held a series of technical positions with IT companies including Byzromotti Design, Bell Labs (in research and development), Zilog, and Xerox’s Palo Alto Research Center (PARC).