Many job seekers have long suspected their online employment applications disappear into a black hole, never to be seen again. Their fears may not be far off the mark, as more companies rely on technology to winnow out less-qualified candidates.

Recruiters and hiring managers are overwhelmed by the volume of résumés pouring in, thanks to the weak job market and new tools that letapplicants apply for a job with as little as one mouse click. The professional networking website LinkedIn recently introduced an "apply now" button on its job postings that sends the data in a job seeker's profile directly to a potential employer.

While job boards and networking websites help companies broadcast openings to a wide audience, potentially increasing the chance the perfect candidate will reply, the resulting flood of applications tends to include a lot of duds. Most recruiters report that at least 50% of job hunters don't possess the basic qualifications for the jobs they are pursuing.

To cut through the clutter, many large and midsize companies have turned to applicant-tracking systems to search résumés for the right skills and experience. The systems, which can cost from $5,000 to millions of dollars, are efficient, but not foolproof.

Ed Struzik, an International Business Machines Corp. expert on the systems, puts the proportion of large companies using them in the "high 90%" range, and says it would "be very rare to find a Fortune 500 company without one."

At many large companies the tracking systems screen out about half of all résumés, says John Sullivan, a management professor at San Francisco State University.

No wonder: Starbucks Corp. attracted 7.6 million job applicants over the past 12 months for about 65,000 corporate and retail job openings; Procter & Gamble Inc. got nearly a million applications last year for 2,000 new positions plus vacant jobs. Both companies use the systems.

Although they originally evolved to help employers scan paper résumés into a database, do basic screening and trace an applicant's path through the interview and hiring process, today's tracking systems are programmed to scan for keywords, former employers, years of experience and schools attended to identify candidates of likely interest. Then, they rank the applicants. Those with low scores generally don't make it to the next round.

The screening systems are one way companies are seeking to cut the costs of hiring a new employee, which now averages $3,479, according to human-resources consulting firm Bersin & Associates. Big companies, many of which cut their human-resources staffs during the recession, now spend about 7% of their external recruitment budgets on applicant-tracking systems, the firm says.

At PNC Financial Services Group, which has used the tracking software for 15 years, an applicant for a bank-teller job is filtered out if his résumé doesn't indicate that he has two to three years of cash-handling experience. PNC emails rejected applicants within a day, suggesting they search its website for jobs for which they are better qualified, says Jillian Snavely, senior recruiting manager.

Mr. Infante is trying to figure out how to develop a test or an assessment system to rate band teachers.

A recruiter reviews applicants who make it through the first cut, which includes the résumé screening and a brief questionnaire about relevant skills. Those applicants get a live or automated phone interview.

Related Articles:

How To Avoid Getting Fired: Never Do The 10 Things

Job Seekers: 10 keys to Success

The Resume is Not Dead, it's Just Evolving

How to Ace an Elaborate Job Interview

Top 5 Easy Tips for Making Your Resume Stand Out

7 Ways to Impress Recruiters with Your Resume