It used to be difficult to determine whether you were getting paid fairly compared to people with similar experience doing the same job. That has changed in the internet era, as a number of websites exist where people openly share salary information.

Most professionals (82%) said they feel well-informed about what they should be making, and 73% said they have checked how their salary compares using online resources, according to a new study from Robert Half. That's up from 54% in a similar survey two years ago.

People work in an office.

Know what you should be paid and talk to your boss about it. Image source: Getty Images.

Many feel underpaid

Less than half of those surveyed (47%) feel that they are being paid what they are worth. That could become a major problem for employers as a hot job market makes it easier for people to switch jobs.

"Workers have more access to information about their salaries, roles and career options than ever before, arming them for conversations with current and potential employers," said Robert Half Senior Executive Director Paul McDonald. "Managers must remain equally knowledgeable, regularly evaluating salaries to ensure they're paying at or above market rates to recruit and retain highly skilled talent in today's competitive hiring market."

The majority of workers (57%) believe that the strong economy has helped their earnings potential. However, 34% are frustrated by the salary increases their company has offered, and 31% believe they would have to leave in order to get a significant raise.

What can be done?

Workers can use the availability of information about salaries to get a raise. It's important to handle that the right way, though -- you don't want to walk into your boss's office and demand a big increase. Instead, take a proactive approach and lay out what you make and what people with similar positions and experience make, and then ask to make a plan to get your salary into that ballpark.

Make it clear that you want to be paid a market rate, but be somewhat flexible when it comes to how you get there. It may take multiple planned raises, but if your company is accommodating (and you like your job), work with it to get where you want to go.

Companies should not force employees to bring salary disparities up. This is something that should be actively addressed. If you're making salary decisions, examine what you pay compared to what your rivals pay. Factor in benefits, workplace flexibility, and other perks. Once you have a picture of where your salaries stand, work with your employees to raise their wages so they are within industry norms.

Workers have options. The job market has been strong, and there are more openings than people to fill them. That makes it imperative for companies to be very proactive when it comes to retaining staff.

It's generally cheaper to keep the employees you have than replace them. Be proactive and make sure you address your employees' concerns before they're forced to leave.