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It’s hard to believe 15 years ago, if you wanted to book a flight, your only option was to wander into a travel agent at your local mall and ask what the options were.
These days, online travel agents and flight search engines have largely taken over from physical stores when it comes to finding and booking air tickets.
It seems a new flight search site pops up every other week, but sadly many have little to differentiate them from all the rest. Occasionally, though, one stands out from the crowd. A company finds a unique angle, a better interface or a more efficient way to sift through thousands of results and come up with the best flight options.
Given I spend far more time than is healthy using these sites, I figured it was time to put several of them through their paces. I wanted to find out – for now at least – which flight search engine is best.
How I Tested
To make this more of a real-world test, I chose five routes that I have either flown in the last twelve months, or will fly shortly. From simple domestic flights to multi-stop, multi-continent routes, they covered a wide range of options.
Given the best time to book flights is supposedly 2-3 months in advance, I chose an arbitrary date of June 27, 2013 to search for all routes. As it’s rare for me to need to fly on a specific day, and also to let me see the range of search options available, I also checked two days either side of that date, for a one-way, economy seat.
There were many ways to determine the “best” result, but I chose the most important metric for many travellers: price. Since not everyone enjoys sleeping on airport floors and taking three days to get anywhere, though, I also looked for other sorting options: number and duration of layovers, total flight times and the like.
Finally, with people increasingly searching for and booking flights on phones and tablets, I also checked out the app or mobile version of each site.
With so many flight search options out there, narrowing them down to a manageable number was a challenge. In the end, I decided to test five sites:
– one I use all the time (Skyscanner)
– one I’ve recently found that seems promising (Adioso)
– one has been around for ever (Kayak)
– one we featured on the site in our first month (Hipmunk)
– one random selection I’ve never used before (Momondo)
I loaded each site in a new, incognito browser window. Flight booking sites are notorious for using cookies to remember your searches, and present higher prices to repeat visitors. I then performed my searches, as well as doing spot checks via mobile and app versions on an Android phone.
So How Did They Fare?
The raw numbers are below, and they throw up a few surprises. Skyscanner, my usual go-to site, came dead last on the most complex routing — a flight from Ho Chi Minh City to Melbourne and then, a week later, on to Seattle. In fact, other than a five dollar saving on one flight, it was never the cheapest option.
Hipmunk failed to pick up the budget flights from Christchurch to Kuala Lumpar that all other sites did, at a cost of over $350. Along with Adioso, it didn’t include the cheap Ryanair flights from London to Frankfurt either. I refuse to fly that airline so it wouldn’t have affected me personally, but it was still an unexpected result.
|Ho Chi Minh City – Melbourne – Seattle||$2,099||$1,627||$1,557||$1,849||$1,761|
|Christchurch – Kuala Lumpar||$437||$444||$435||$471||$798|
|San Francisco – New York||$188||$171||$151||$160||$160|
|Sydney – Amsterdam||$1,152||$1,142||$1,147||$1,220||$1260|
|London – Frankfurt||$26||$31||$108||$43||$104|
Of course, there’s more to finding the best flight than just saving money. After spending hours in front of each site, there were clear pros and cons to each one.
Pros: Powerful, flexible search options. You can choose entire weeks, months or years, to/from a country rather than a specific city, or even to ‘Everywhere’ if you just need to get away.
It’s easy to sign up for daily price alerts for a given route, and the mobile app is fast and simple to use. In fact, it’s actually easier to use than the desktop version when doing a flexible search that spans two or more months.
Cons: Occasional odd search results (flights with layovers that don’t show any details until the booking screen). More obscure routes or flights well in the future often have limited results when searching by week or month, requiring loading each day individually.
Multi-part bookings are typically not shown by default, making it easy to miss out on the cheapest flight options.
Pros: The most obvious feature is the natural language search – “London to New York in mid June”, or “Sydney to Bangkok next month for 7 to 10 days”. Even better, it actually works.
The “best” vs “cheapest” filter is straightforward, and being able to select different days to view without changing screens is a real time saver. Price alerts are easy to set up.
Cons: The biggest issue is lack of a mobile site or app. The site looks great on the desktop, but it is slow and has display issues on a phone. For now, if you’re using Adioso, it’s best done on a bigger screen.
Pros: The site is slick and fast (in the initial stages of a search, at least), on desktop, mobile and Android app.
Cons: Unable to search for more than one day at once, and with each day’s updated results taking 10-20 seconds to display, the site is not ideal for those with flexible itineraries.
While prices for surrounding days are shown in graph form, they were often several days old and needed refreshing one by one. The multi-city option sounds great, but failed to turn up any results in my test (searching each leg individually did, however).
Pros: A simple interface with a working multi-stop option. Being able to see a configurable number of days each side of a given search date is great for spotting cheap options quickly. The site works well on mobile and app versions as well.
Cons: Consistently more expensive than rivals in these tests.
Pros: Although the interface can be a little jarring, it is an effective way of seeing flight lengths and departure/arrival times. The default “Agony” filter does well to surface the best combination of price, length and layover. Having multiple search ‘tabs’ at the top of the screen is a handy feature.
Cons: Limited options for flexible searches – up to two days before or up to two days after a given date. More expensive than rivals, even when filtering by price.
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So Which Is Best?
After all that, the obvious question is: which flight search site is best? As a long-time Skyscanner user, I’m surprised to admit that actually, if you’re using a desktop browser, it’s probably Adioso. With fantastic natural language search, consistently-lowest fare options, and a great interface, I’ll be using it a lot more myself in the future.
If you’re on a mobile device, though, I’d still recommend Skyscanner. The other options aren’t bad, but the fast, easy to use app and broad range of results gives it the edge over the competition.
All that said, no flight search engine is perfect or shows every available option. Some airlines (Southwest in the US, for example) don’t allow themselves to appear, and each search algorithm is a little different, especially with what could constitute a connection. Don’t forget to check your favourite airline sites individually if they aren’t showing up in search results.
Which site do you use when searching for flights, and why?
Main image via Timothy Tolle,