The federal government plans to shut 40 percent of its computer centers over the next four years to reduce its hefty technology budget and modernize the way it uses computers to manage data and provide services to citizens.

Computer centers typically do not employ many people to tend the machines, but analysts estimate that tens of thousands of jobs will most likely be eliminated.

The federal government is the largest buyer of information technology in the world, spending about $80 billion a year. The Obama administration, in plans detailed Wednesday, is taking aim at some of that by closing 800 of its sprawling collection of 2,000 data centers. The savings, analysts say, will translate into billions of dollars a year and acres of freed-up real estate.

The government is following the lead of private business. For years, companies have been using software that shares computing tasks across several machines in a data center. The task-juggling technology enables computers to run at far higher levels of efficiency and utilization than in the past, doing more computing chores with fewer computers and fewer data centers.