Google Flights, Skyscanner and KAYAK look different but do much the same job: they gather fares from many airlines and travel agencies on one screen, then send you to a seller when you pick a ticket. So instead of asking which search engine is cheapest, it helps to ask what each one shows best, and where you will finally pay. This is a research comparison based on the three services' official help and information pages, the Korea Consumer Agency, the Korea Fair Trade Commission and Korean law, all checked on October 14, 2026. I have not compared live fares on the same route or tested whether any prediction comes true, and feature names and coverage vary by country and over time.
None of the three sells you the ticket
Google says choosing a fare on Google Flights normally takes you to an airline or online travel agency (OTA) to buy it. It works with more than 300 partners, says those partnerships do not affect the order of results, and notes that airlines without a partnership may not appear. Skyscanner calls itself a travel search engine that takes no payments and earns referral fees from airlines and travel companies. KAYAK also says it does not sell tickets; it earns commissions per click or booking and labels its sponsored listings.
This matters when something goes wrong, because the search engine is not the company you contact. All three say changes, cancellations and refunds follow the rules and customer service of whoever issued the ticket. KAYAK has a 'Book on KAYAK' option that completes the booking on its own site, but it says a third-party provider fulfils it. Two results that look like the same flight can come with different refund terms if the sellers differ.
Google Flights: watching a route you have already chosen
Google Flights splits results into 'Best' and 'Cheapest' tabs and warns that the cheapest list can include travel-agency itineraries or self-transfers with trade-offs. It can track a route or a specific flight and email you about significant changes, sometimes adding a warning that prices are likely to rise, with an estimate and a confidence level. Google's 2023 announcement says tracking needs a signed-in Google account. Price insights show whether today's fare is low, typical or high for the route, and on routes with enough data Google also shows when it has usually been cheapest to book.
The bags filter shows fares with checked or carry-on bag fees included. Google says displayed prices include taxes and airport charges, but extras such as bags or card fees can vary by seller, and calendar prices refresh roughly daily, so they can lag behind live fares. Since November 2025 its AI-powered Flight Deals beta, which takes a trip description in plain language and highlights fares at least 20% below typical, has covered more than 200 countries and territories, including Korea. Google's price guarantee applies only to US-based users on itineraries departing the US, so it does not cover trips from Korea.
Skyscanner: when the destination or dates are open
Skyscanner's strength is the 'Everywhere' search, which lists destinations from your airport by price, along with searches across a whole month or the cheapest month. Its help pages say month-view and Everywhere prices are estimates based on what other users recently found, not live fares; the current price appears once you pick a date. Price alerts require an account and remember only the route, dates, travellers and a direct-flight preference, so other filters are not applied.
The app's 'Drops' feature lists flights from your airport whose price has fallen by 20% or more. Skyscanner shows combinations of one-way tickets on different airlines, or self-transfers, when they are cheaper, and explains that these are not protected like codeshares: each ticket has its own change rules, and bags may need re-checking. Its 'Recommended Provider' badge cannot be bought and is reviewed monthly on quality, price accuracy and booking completion. There is a Korean site (skyscanner.co.kr) with a Korean help centre, and Skyscanner says its prices include an estimate of taxes and mandatory charges.
KAYAK: deciding whether to buy now or wait
KAYAK's distinctive feature is its price forecast. According to its help pages, it predicts whether a route's fare will rise or fall within the next seven days, suggests buying now or waiting, and shows a confidence level. Its About page gives a 30-day horizon instead, so the two disagree, and KAYAK says forecasts cannot be guaranteed. Price alerts usually arrive once a day, with optional real-time alerts for big moves of around 10%. Alerts and the Explore map are based on prices other users found in the previous 48 hours.
Hacker Fares, which pair one-way tickets on different airlines, are called 'KAYAK Mix' on the Korean site. Fares include taxes and fees but not checked bags or seat selection; the Fee Assistant estimates bag and payment fees. You can widen dates by three days either side, weekends or a whole month. The Korean site (kayak.co.kr) shows prices in won and has an 'Ask AI' button, and KAYAK says it adds no booking fee. Some discounted fares hide the airline's name until after purchase, so read the conditions.
More important than the search: where you pay
In October 2024 the Korea Consumer Agency compared prices 800 times across eight routes and ten OTAs and found the OTA price higher than the airline's own site in 71.4% of cases. The gaps were small, but OTAs often add their own fee to the airline's, so their cancellation fees were equal or lower in only 10.3% of cases. The agency and the Fair Trade Commission have warned that buying through an agency can mean paying both the airline's and the agency's cancellation fees, and that some agencies do not process cancellations outside business hours.
Complaints are rising. Requests for damage relief over airline tickets grew from 1,705 in 2023 to 2,532 in 2024 and about 3,200 in 2025. In June 2026 the Fair Trade Commission issued correction orders and fines totalling KRW 10 million to Trip.com for selling tickets without mail-order registration and refunding in airline vouchers, among other problems. On the other hand, after the commission corrected the terms of eight Korean travel agencies in December 2023, tickets bought from them on 22 airlines can be cancelled free within 24 hours. Wherever you search, check the seller's name and refund terms on the final payment page.
Total fares and bags: reading the price on screen
Article 62(5) of Korea's Aviation Business Act requires airlines, general sales agents and travel agencies to make the total amount a passenger will actually pay easy to see. Its enforcement decree requires them to state one-way or return, flag amounts that can change such as fuel surcharges, and emphasise the total. Violations can bring a fine of up to KRW 5 million, and the consumer agency says the rule has applied since July 15, 2014. A 2025 amendment requires the transport ministry to inspect compliance and publish the results.
That article places the duty on airlines and travel agencies, so a search engine's price has to be read against what each service says it includes. All three say they include taxes and mandatory charges, but bags and seat selection may be extra; Google's bags filter and KAYAK's Fee Assistant help fill the gap. The consumer agency has also warned that card fees and exchange rates can make the charged amount differ from the booking price, so check whether you will be billed in won before paying.
Our three picks
- Watching a route with fixed datesGoogle Flights
Use price insights, tracking and the bags filter to follow a route you have chosen. Tracking needs a signed-in Google account.
- Open destination or monthSkyscanner
Use Everywhere and month searches to widen the shortlist. Calendar prices are estimates, so check the live fare after picking a date.
- Buy now or wait?KAYAK
Use the price forecast, KAYAK Mix and the Fee Assistant to weigh the conditions. A forecast is not a guarantee.
Side by side
| Question | Google Flights | Skyscanner | KAYAK |
|---|---|---|---|
| Sells tickets itself? | No; links to sellers | No; takes no payments | Mostly no; some bookings fulfilled by third parties |
| Price alerts | Tracking emails (sign-in needed) | Email alerts (sign-in needed) | Daily, or instant on big moves (sign-in needed) |
| Help deciding | Low/typical/high insights, when to book | App Drops (fares down 20%+) | Seven-day forecast with confidence |
| Open-date search | Date grid and calendar (refreshed about daily) | Everywhere, month and cheapest month | ±3 days, weekends, whole month, Explore map |
| Bag fees | Bags filter shows inclusive fares | Optional extras may be added at checkout | Estimated by the Fee Assistant |
| Separate-ticket combinations | Separate tickets under Cheapest | One-way combinations, self-transfers | KAYAK Mix (two one-ways) |
| Korean site | Korean interface, won | skyscanner.co.kr, Korean help centre | kayak.co.kr with Ask AI |
| Changes and refunds | Airline or agency that sold the ticket | Provider you booked with | Provider you booked with (no KAYAK refund policy) |
Where I would start
With fixed dates I would watch the route on Google Flights; with an open destination or month I would widen the shortlist on Skyscanner. When torn between buying and waiting I would glance at KAYAK's forecast without treating it as a promise. Before paying, I would put the same ticket next to the airline's own price and check the seller's cancellation fees, customer-service hours and whether bags are included.
