What's your pay potential? LinkedIn, Glassdoor shine light on salaries.

Money isn't everything, but it counts for a lot at work. That's why work-related websites like LinkedIn and Glassdoor are adding new online tools to help professionals understand their salary potential.

LinkedIn, which calls itself the social network for professionals, is adding a service that provides members with pay information for a variety of jobs, including a break-down by such factors as location, industry, education, and experience. It's based on anonymized data submitted by LinkedIn members, including details about base pay and other compensation, such as bonuses and stock grants.

The new service comes two weeks after Glassdoor, a competing online job site, introduced a feature that promises to help workers determine their "personal market value" by comparing their current job title, salary, and related information with data from other workers and current hiring trends.

Glassdoor's site already showed information about median salaries and perks, along with employees' reviews of what it's like to work at various companies. It says the new feature can be useful for job-seekers as well as workers who might want to negotiate a raise from their current employer.

Both new services are free and promise to go beyond more generic salary tools – offered by job sites like Indeed, PayScale.com, and Salary.com – by combining sophisticated computer analysis with the most up-to-date information gleaned from workers, labor reports, and other sources.

While LinkedIn officially announced its service Wednesday, spokesman Dan Shapero said the company has been quietly inviting some members to contribute their compensation data in recent months. The "LinkedIn Salary" feature is launching with data from 1 million professionals in the United States, Canada, and Britain. LinkedIn may not have data for every job, Mr. Shapero acknowledged, but he predicted the service will improve as more people participate.

LinkedIn Inc., based in Mountain View, Calif., may add more kinds of information in the future, he added, such as suggestions about particular skills that can boost salaries in a particular occupation. LinkedIn recently began offering training suggestions for workers, based on their current jobs or career track, which tie into the online courses offered by its Lynda.com subsidiary.

Glassdoor has been on the frontlines of a wave of new internet tools aiming to bring some transparency to salary data, first offering a means for users to anonymously share data in 2008. Previously, salaries tended to be closely guarded by both employers and employees, as The Christian Science Monitor reported at the time:

"How much do you make?" has long ranked as an impolite question in polite circles. Salaries remain shrouded in secrecy, reigning as one of the last taboo subjects.

Now that "Shhh, don't tell" attitude is beginning to crumble as the Internet offers new ways to gather and post information. With a few clicks of a mouse, Web users can browse salary sites to find general salaries for various positions. A new entrant, Glassdoor.com, allows anyone to find and anonymously share salary details about his or her job at a specific firm and location. Launched in June, the website went global last month, providing salaries in more than 100 countries.

"It's a level of transparency that hasn't existed before, so it's initially uncomfortable," says Robert Hohman, CEO of Glassdoor. "But it's empowering. Being paid fairly for our work affects us emotionally, and having that income affects our life. People want to know, 'What am I worth as a software engineer with five years' experience?' "

Both LinkedIn and California-based Glassdoor, Inc. promise to keep individual users' pay data confidential. But spokesmen wouldn't rule out the possibility of the companies making money in the future by aggregating the information – in a way that keeps individuals anonymous – and selling it to employers who might find it useful to calculate pay scales or salary offers.

While both companies promote their website as a useful service for workers, they make money by selling job listings and hiring tools to employers and recruiters. So each company wants to offer helpful features that keep workers coming back to their sites.

LinkedIn recently agreed to be acquired for $26 billion by Microsoft, which wants to augment its own commercial software – including email and calendars used by workers, as well as management and corporate sales programs used by employers – by incorporating LinkedIn's extensive database of professionals and their resumes.