Best Airfare Search Engines for International Flights

If you like doing your own research instead of booking through a travel agent, below is a list of search engine sites that I have used and continue to use when scanning for better price deals for international flights.
Some airlines do not participate in search engines; therefore, if there's a particular airline that you don't see in the list, you may want to visit their official website and compare prices.
Note: Google Flights used to be a great and useful tool if you wanted to get a rough idea of the price range per different departure and return dates up to months ahead, but it's been inaccurate as of the time of this post.

Tip: In the US, your point of departure can also make a difference on how much you pay in total for travel. You may get a better deal if you can travel domestically form your home state to catch an international flight from one of the airports listed in the US States below:
  1. New York
  2. Boston (especially flying Delta Airlines)
  3. Washington DC (especially if departing from BWI or IAD) 
  4. Los Angeles (especially if travelling to Asia)
  5. Chicago