When you need to buy flight tickets, you can always perform a search on Google Flights for good prices. But you're missing out on potential cheap flights if you don't use these websites to find the best deal for your money.

All these cheap flight websites will ask you to first choose your place of departure and destination, along with dates, the number of people traveling, and whether it's a round-trip. But after that basic information, each website has a different purpose thereafter.

Best Website to Book Flights: Skyscanner

For years now, Skyscanner has been our constant recommendation for the best website to book flights. It's so easy that anyone can use it, and it has mini-sites across the world with localized customer care.

Skyscanner is an aggregator. This means that it will check for the best flight prices across dozens of sites, including both official airline portals as well as other travel aggregators like Skyscanner itself. The idea is to find the cheapest flight price possible, and Skyscanner has regularly delivered this in spades.

In fact, you can actually get even better deals through a few tricks and tips in using Skyscanner. For example, if your travel dates are flexible, Skyscanner uses historical data to show the cheapest month you can travel between two destinations. You can also see any whole month's prices. Skyscanner lets you compare flight prices at nearby airports, getting a much better deal if you're willing to put up with a little bit more commute by land. These small things add up to save some big bucks.

Get Alerts When Tickets Are Cheapest: Hopper

Hopper is a mobile app, but it does something that none of the websites manage to do. Using a variety of historical data points about flight prices across the year, Hopper specializes in figuring out when the flight is at its cheapest.

Here's how it works. Airplane prices go up and down, and just because you book in advance doesn't mean you have got the best deal. Hopper removes that guesswork. You set up the destination you want to go to, and the desired dates of travel. In the background, Hopper will silently watch prices for that route. Once it determines the price is at its lowest, you'll get an alert telling you to book it. Simple, right?

I've tried out Hopper for multiple flights and found it not only gave me the best price possible but also recommended shorter flights at the same price. Hopper also tries to predict how much higher the price might go, in case you want to wait. It's one of the best apps to get cheap airline tickets.

Download: Hopper for Android | iOS (Free)

Best Website for Cheap Last Minute Flights: Kiwi

In the travel industry, it's common knowledge that last-minute flights cost more. No, airlines don't try to discount their tickets to fill up seats. But what you can do instead is use Kiwi, a travel aggregator similar to Skyscanner, and its smart tools.

Kiwi enables a couple of things that you don't get with other tools like Skyscanner. First, you can add multiple points of origin. So instead of searching for flights from Philadelphia to London, you can search from Philadelphia and New York to London. You can also change a place to include other airports around it, so it won't just say London but other nearby airports too.

Kiwi also uses its algorithms to find cheaper flights by adding a layover between your travel. Sure, layovers can often be a pain in the neck, but when your flight price reduces by 20%, you don't seem to mind as much. And that's a hefty percentage when it comes to last-minute flights.

Best Website for Secret or Hidden Cities: Skiplagged

Skyscanner, Kayak, Ixigo, Cleartrip, and all these other popular flight search aggregators can't show you "hidden cities". Skiplagged can. And chances are, you'll save big amounts with it.

Hidden cities are layovers that the flight operator doesn't disclose. For example, when you search for flights from Dallas to Los Angeles, the carrier won't always show you options on the New York-Dallas-LA flight. It's a short layover in Dallas and they don't want to spend too much time there. So Dallas is a "hidden city" on that path. And with Skiplagged, you can still book a seat on that flight.

While these hidden city deals are usually cheaper, there are some restrictions. Hidden city flights only allow you to use carry-on luggage, you can't check anything in. And such flights don't count towards your frequent flyer points either. But hey, the savings are so good that it's one of the best-kept secrets of expert travelers.

Best Website for Flight Deals: All The Flight Deals

Airlines, travel agents, and other travel companies often offer steep discounts or great deals on airfare. You can't track them all, which is why some sites and bloggers specialize in doing that. Well, All The Flight Deals is an aggregator for those sites and bloggers, giving you the best deals from multiple sources, much like Skyscanner gets the best prices from multiple websites.

It's simple. Key in the city you'll be flying out from. You can choose filters like verified deals, non-stop flights, or the continent you're interested in traveling to. In a minute, you'll see a bunch of deals that fit your needs. Click what looks interesting, follow the usual steps to book a ticket, and you're good to go.

All The Flight Deals is even better if you refine these settings the first time and then set up an email alert. You don't need to go to the site every day, and instead get a simple newsletter whenever there's a new deal that matches with your settings.

Follow Airline Flight Deals on Twitter

While All The Flight Deals does a great job, it will only alert you to good deals from your city. For the best deals going around, there is only one account you should follow: @TheFlightDeal. You're almost guaranteed to never miss a great discount on flights again.

Flight tickets are one part of travel anxiety. But these sites should help you minimize your travel stress and have an enjoyable vacation or a business trip.