With the click of a mouse and for an $80 fee, anxious parents can find what the odds are that their sons and daughters will be accepted into universities such as Brown University, Dartmouth College and Yale University on Web sites like ThickEnvelope.com and CollegeConfidential.com.

Grant Ujifusa, one of the founders of ThickEnvelope.com, said the purpose of the Web site is “to provide a credible second opinion about a student’s chances” of getting into a university. Ujifusa and his business partner, fellow Harvard alumnus Richard Sorensen, came up with the idea over lunch in August 2003. After accompanying his son on several campus tours, Sorensen complained about their inadequacy, Ujifusa said.

“He came back from those sessions completely befogged. He thought there ought to be a better way,” Ujifusa said.

For $79.95, students and their parents can fill out ThickEnvelope.com’s online application and, within seconds, are directed to a page detailing the student’s chances of being accepted into each of the 80 colleges on the site.

Students using the service must provide information such as SAT I and SAT II scores, numerical or percentile class rank, class size and grade point average. There is also a section on the application to list the students’ extracurricular activities, community service and leadership skills.

“We think we can model reality,” Ujifusa said.

For example, Ujifusa said, SAT I verbal scores carry more weight in the admissions process than SAT I math scores because fewer students score a perfect 800 on the verbal portion of the SAT I. More specifically, essays at Brown are not as important as teacher recommendations, while interviews count for next to nothing, he said.

Other Web sites offering a statistical evaluation of prospective applicants work with similar formulas.

Dave Berry, founding partner of CollegeConfidential.com, said the Web site uses a formula that takes into account scores and grades to calculate a student’s academic index. The statistics — combined with an “in-depth” analysis of writing samples, legacy status, examples of leadership and other factors — determine the student’s chances. The service costs a total of $89.

But Berry said his Web site is unique in taking into account applicants’ personal qualities.

“That’s the differentiating factor between us and Web sites like ThickEnvelope.com,” he said. “In my opinion, there is no way that a computer can actually differentiate the subtleties about non-quantitative things.”

But some parents prefer not to get too personal.

Susan Ruben of Cleveland, Ohio, said she used ThickEnvelope.com for her 11th-grade son. She said she preferred ThickEnvelope.com’s somewhat formulaic analysis.

“The purely statistical model appeals more to me, because it is less subjective as opposed to speaking to one person,” she said.

Ruben said she first learned about ThickEnvelope.com in late January. Without telling him, she said, she entered her son’s statistics.

“There were schools where he was in the 80 and 90 percentile range, and there were others where he was in the 20 percentile range,” she said.

Ujifusa said the probabilities the service can give a student range between 5 and 90 percent.

Ruben said although the $80 price tag was a shock, the service was worth it.

“I thought my experience was positive and I would recommend it to others,” she said.

Nancy Bratteli of Paris, Texas, said she decided to use CollegeConfidential.com because her son John, then 18, attended a small-town high school.

“We just didn’t know how he would stack up against the best students in the country,” she said.

Bratteli said she worried about her son’s chances after reading online and in the Princeton Review “how many ‘1600s’ were not getting into top schools.”

Bratteli said the process was efficient and accurate.

“Our son was accepted at Rice, MIT and Caltech, and was waitlisted at Princeton, which was exactly Mr. Berry’s prediction,” she said.

Despite favorable reception from parents, high school counselors and college admission officers remain wary of online prediction services.

“When people are sort of in the for-profit business, you have to be a little bit skeptical about it,” said Michael Goldberger, Brown’s director of admissions.

Goldberger said quantitative factors like SAT scores are only part of the story when it comes to Brown admissions.

“To try and say your chances of admission are X and Y based upon your GPA or SAT scores goes so short of what we look for,” he said.

But Ujifusa said statistic evaluations are comparable to daily weather forecasts.

“It’s like saying that there’s a 40 percent chance of rain tomorrow,” he said. “It’s a probability.”