15 signs you're underpaid

Feeling underpaid can be one of the most disheartening aspects of work.

"It stands to reason, because for many, compensation is a concrete litmus test of how well you're performing and progressing on the job - and how highly you're valued," says Lynn Taylor, a national workplace expert and the author of "Tame Your Terrible Office Tyrant: How to Manage Childish Boss Behavior and Thrive in Your Job."

According to the 2016 Global Workforce Study, which surveyed more than 31,000 employees around the world, almost half of US employees believe they are being paid unfairly compared to workers who hold similar jobs either at their own or other companies.

And a 2016 PayScale report is even bleaker. About two-thirds of surveyed workers said they felt they weren't paid what they're worth. What's more, feeling underpaid was one of the top reasons employees said they quit their jobs.

Interestingly, people are often wrong about whether they're paid fairly or not. As PayScale found, two-thirds of people who are paid their market value feel they're underpaid, and even 35% of people who are paid above their market value think the same.

"The topic of employees' salaries is well guarded by most companies, so it's not always easy to figure out how your pay compares to your colleagues'," says Taylor. "If you're willing to invest the time and research or look for the signs, however, you'll be better informed as to whether you should ask for a raise or walk."

Here are 15 signs you're paid less than you should be: