Expedia's online travel sites are introducing tools designed to show the true cost of flying.

The features announced Tuesday will list the fees for checking bags and cancelling a reservation in addition to the ticket fare. Those fees typically remain hidden until a traveler is ready to buy a ticket.

Expedia is hoping the additional transparency will help its sites, which also include Travelocity, Orbitz and Hotwire, to stand out from rivals like Priceline.com's Kayak and Google's extensive index of flight information in its dominant search engine.

Added airline fees have been a sore spot for travelers since American Airlines began charging to check bags seven years ago, but they are here to stay.

Baggage and cancellation fees generated $6.5 billion in revenue for airlines last year, a 7 percent increase from 2013, according to the U.S. Department of Transportation.

The airline industry is fighting proposed government regulations that would require carriers to spell out their baggage and cancellation fees alongside their ticket prices.

Expedia's sites also are going to analyze airline pricing trends to advise travelers when there are likely to get the best deal for a ticket to a destination on their business or vacation itinerary.