A Complete List of Free Flight Search APIs in 2021

I’d been talking a lot about automated flight search using Python to find cheap airline tickets on this blog. At the very core of my travel hacking project, such as Hidden City Ticketing always lies a flight API to be queried. In this post, I will have a look at the APIs, which are currently available and what limitations these have. I will also briefly touch on APIs that are widely recommended on the Internet but are no longer functional.


One of the easiest ways to get dive into the world of automated flight searching is through the Skyscanner API provided through RapidAPI. On the plus side, it comes with unlimited requests and query sessions and a variety of endpoints. The overall rate limit is capped to 50 requests per minute, which should be a sufficient amount of requests for most personal projects. One major limitation is that live pricing is done through sessions, which means that if you maintain an unhealthy traffic (such as scraping prices without resulting in bookings), you can be blocked. Besides the live pricing, the Skyscanner API also comes with a functionality to get cached results for a specific date and time combination or route. This can be good for popular routes such as London to New York but might be less effective for less demanded routes. What I like about Skyscanner is that they allow querying different locales, which can help you to save some money by changing your Point of Sale, I will write more on that in the future.


An API, which I’ve talked about before quite excessively, is the Kiwi.com. Kiwi.com is a quite unique flight search, as they combine both full service and low-cost carriers into a single result and combine these on a (virtual) ticket. What I like about the Kiwi.com API is that you can play around using their provided API token (picky) and its fast, reliable endpoints. Additionally, it comes with realtime pricing. One downside I’ve noticed is that the multistop API isn’t particularly smart. Instead of combining a return with a third flight, it would always search for three individual flights. Like with Skyscanner API you should maintain always maintain healthy traffic and apply for an API key once your application goes live.


Jetradar is another meta-search engine, similarly to Skyscanner or Kayak, that allows searching for flights. You can access the API through travelpayouts. With the standard account, you will have access to cached prices of flights searched throughout the past two days. From my own experience, I’ve noticed that this can reveal some pretty good deals. If you want access to their live search API, you will have to apply for access. Like with the previous two, you will have to provide a viable business model and show that you are providing healthy traffic and not just pulling the results.

Google Flights/QPX express (deprecated)

The Google Flights was an extremely powerful flight search service that facilitates the purchase of airline tickets through third-party suppliers such as Airlines and OTAs. It came with a free quota of 50 queries per day. It was switched off on April 10, 2018.

Unofficial Momondo API by 5ms (deprecated)

On GitHub I found an unofficial Momondo API by a programmer called 5ms. This php code was basically a wrapper for the former Android API of Momondo and was extremely powerful and widely used by travel hacking projects. In 2021, the endpoints are no longer operational and only return a 403 code.

Unofficial Expedia Webscraping (deprecated)

Not necessarily an API, but also a JSON response, yielded by a former version of the Expedia website. ScrapeHero has automated the search process by providing a wee Python script, that searched, downloaded and extracted the results. However, the Expedia site no longer returns the JSON data in the header and, therefore, rendering the script useless. If you have a legit project that results in healthy traffic, consider becoming an official partner of Expedia. In the past, I’ve heard from friends that they are quite supportive, even towards startups.

I hope this post gave you a good overview of the state of the free flight search APIs out here. If you know of any other API that should be added to the list, then feel free to reach out to me.