In my discussions with friends and colleagues they are often amazed by the airfare deals that I am able to find. Flights to Europe for $200, Bali for $500, New Zealand for $275. At the same time, I am amazed by the prices that business travelers pay; $750 for a flight from Detroit to Pittsburgh. The difference between the two is flexibility.
More than anything else, flexibility is the key to finding a cheap flight. To score a great deal you MUST be flexible in either dates or destination, and to score an amazing deal you need to be flexible in both. I often have people ask me to find them a deal to so and so over specific dates. No matter how hard you look you aren't going to be able to find a major deal. The more flexibility you have the greater your potential cost savings.
The 3 main tools at your disposal when looking for flexible flights are listed below with some of the highlights of each:
This is a great tool for looking at multiple destinations over a specific set of dates. You can essentially plug in any dates, see a map of the world, where you can fly and at what prices. It is also great at looking at different dates to a specific location. You can set a particular origin and destination and view a calendar of all available prices/dates
Google Flights: Flexible destinations over specific dates
Google Flights: Flexible dates to a specific destination
Set your origin and see a map of the world with prices. This is a good tool if you are flexible in both dates AND destination. The downsides to this are that there is a lag time in when prices are updated and sometimes great deals come and go before they show up here. Furthermore, since the data is based on actual flights booked, more obscure origins and destinations may show limited results.