Possibly one of the top flight fare research tool and we highly recommend this one if you’re searching for low international fares. Momondo runs a thorough search across multiple international airlines and has numerous information displayed on their page to help you narrow down the best flight.
After you input your flight information and run the search, they have an estimated fare prices chart for each day shown above on the results page and in the top right hand corner “Flight Insight for (departing city) to (destination)”, they also break down when fares are cheapest, how far in advance to book, cheapest airlines (as shown above) and so on. Click on the top navigational bar from the flight insight page for more detailed information. You also have the option to set up Fare Alerts!
The Miles 101 