WASHINGTON -- People planning for retirement have a new tool: a fast and easy online estimator for their Social Security benefits.

The Social Security Administration unveiled its new retirement estimator on its Web site yesterday. It takes just a few points and clicks and some personal information to produce benefit estimates within a few minutes.

The new calculator (ssa.gov/estimator) will be followed this fall by an updated online application for benefits that Social Security Administrator Michael Astrue promises will reduce application time from the current 45-minute process to 15 minutes -- and eliminate the need for follow-up visits to agency field offices.

"These initiatives will help us better handle the baby boomer wave and make it easier for the public to do business with us online," Mr. Astrue said.

Currently, workers get an annual benefit estimate mailed to them. It's based on prior earnings but assumes people's salaries stay the same until retirement age. The online calculator supplements the annual mailing but won't replace it.

The online calculator permits future retirees to create a more accurate estimate of benefits since people can factor in a higher estimate of their upcoming earnings. People also can factor in different alternatives for retirement ages.

The calculator replaces a laborious online calculator that required people to type in their earnings history, which can involve guesswork for people who don't keep voluminous records.

The new version uses the Social Security database to provide accurate earnings information, though the calculator requests the most recent year of earnings since there's a lag in getting salary information into the Social Security database.

There's inherent uncertainty about the estimates since for many people it's not easy to predict future earnings. That's especially the case for younger workers.

"The closer you are to the retirement age, the more accurate this estimate is going to be," Mr. Astrue said.

Mr. Astrue said the agency had taken steps to make sure people's personal information wouldn't be divulged.

The agency has worked up a new security system for when it accepts online applications, though many foreign-born recipients will still be required to furnish proof of retirement age at field offices.