More workers than ever are sharing salary info—here's what could happen if you open up

Salaries are no longer secret, at least not to most millennials.

The Cashlorette, a Bankrate company, found in a survey of more than 1,000 U.S. adults that 63 percent of 18- to 36-year-olds say they have shared salary data with an immediate family member, 48 percent have shared with friends and 30 percent have shared with co-workers.

That's in comparison to 41 percent of baby boomers who've shared that info with family, 21 percent who've shared with a friend and 8 percent who have shared with a co-worker, the survey says.

So, what happens if you tell a co-worker your salary?

According to Traci Fenton, chief executive officer of leadership firm WorldBlu, it could do some good. Offices have the potential to function better if compensation is shared among bosses and co-workers.

"Everyone gossips about how much people make and everyone's wondering — it's very toxic and wasteful," she says in an interview with career-advice website Monster. "When you're open and transparent, it cuts down on the noise, and allows people to be more efficient."

Sharing salary data can also let you or someone else know if they're not making enough. According to the survey, it could "help you determine if you're actually getting paid fairly, or give you the boost to work up the nerve to ask for a raise."

In , for instance, women, on average, earn less. A study from job-platform website Hired found that, 63 percent of the time, women are offered lower starting salaries than their male counterparts for the same job at the same company. And knowledge can be power.

Sharing your salary data can have its downsides, though. Even for people with similar job titles, pay can vary based on experience and skill-set. If your co-workers discover you're making more than them, it could cause tension and discontent and decrease productivity.

The result of telling a co-worker how much you make will depend largely on your relationship with them. If you have concerns that you aren't being paid fairly, or you want to know your market value, you could instead.

While these tools rely on self-reported numbers and can't take into account your specific circumstances, they can offer useful insight by measuring your pay against your experience and position comparing it to the wages of your peers across the country with the same job title.

If you'd like to try for an increase in salary, check out these three negotiation strategies. If you're already in a job, here are some ways to ask for a raise.

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