If you are a frequent traveller and you travelling dates are flexible, then you can add extra discount to you fly cost using Google Flight tool, it has a price alert feature which can help you to find a cheap ticket. Google flight is one of the best in class tool which will help you to find out
You can use the lowest fare calendar and Graph for your purpose, go to the google flight tool and on the front page you will find a graph like icon at the right side of the page. By clicking on it you will find a graph which shows the cheapest and the most expensive options depending upon the length of the flight you are choosing, here you can find on which date which airline is providing minimum rate for the same length of the flight.
Google flight Tracker
2>flight tracker, google continually tracks the price of the flights on a given route all you need to do is to select a departure and arrival airport and you date of travelling.
Ex- you have set Delhi India as your departure and Sidney Australia as your destination on a specific date what google will do is, google will start tracking the flight and near the specific date whenever the google find minimum price which will be mailed to you on your email id. This is pretty handy and helps a lot in finding the minimum fare flights, you get notice every time whenever the price start going up and whenever prices starts going down.
3> filters using these filters you can eliminate those flight which are unnecessary for you. You can use stops and duration filters which will help you to get your kind of flights. If you are not interested in red-eye flights, you can use the time filter and these red-eye flights will be filtered out form your options
4> the best thing about Google flight tool is it’s explore map. This will help you to flight out all possible flight form a departure to destination. And in addition to this google flights also helps you to find out. plan your trips you can modify your number of stops, you can modify you departure airports, select your time of flight and a lot more using the explore map.