Rankings - API Fortress


A list of the best APIs in each industry. Picked by professionals.


We have always wanted a quick list of the top APIs by industry, but not just from a basic feature vs feature perspective. An actual review of all major components of what makes a good API program.


We did an extensive review of each API, built off of them, and graded them based on the below items:

  • Payload - Is it well organized, human readable, and easy to navigate?

  • Authentication Procedure - Level of difficulty to connect, and if there are various options presented.

  • Reliability of Service - We keep tabs on the uptime %. Seriously.

  • Predictability - Does the service behave as expected?

  • Documentation - A fundamental requirement that unfortunately varies significantly.

  • Ease of Sign Up / Getting an API Key


“The documentation is a masterpiece. Every request and response is explained in great detail. The data structures (despite being very large) can have different layouts based on the application goal, and are available both in XML and JSON. The reliability is good.”


“The documentation is example driven, and explains flows at a high level. The reliability has been flawless to date.”

Google Maps

“The industry leader for a reason, but competitors are catching up.”


“The documentation is as good as we have come to expect from Google. The payloads are detailed, and yet easy to navigate. Excellent reliability and predictable behavior.”

Microsoft Office 365

“A relatively new offering and they came out with a great series of APIs, and all the documentation you could ever want. It is not perfect, but the best in the industry overall.”

Microsoft OneDrive

“Some would be shocked that this was our winner, given the strong competitors in the market. The key for OneDrive was an outstanding data structure, stability, and predictability.”

The Guardian

“The API is compact but achieves its goal well. An example driven set of documentation proves to be very helpful, and the reliability level has been the most reliable in this industry.”


“The documentation is very well done – detailed and up-to-date. The API console allows you to play with all the endpoints without going nuts in the prototyping phase. Request formats and payloads are easy to read and navigate, and the reliability is solid.”


“The documentation is good, and the data structures are simple.”


“Twitter demonstrates how an API program can be a vital part of a company’s strategy. Great documentation, multiple authentication options, a very rational payload, and flawless availability.”


“One the best blogging engines is also one of the best blogging APIs. The documentation is well done and detailed. Making a post using the API is smooth. Superb reliability.”

Getty Images and Shutterstock

“Both contenders performed so well we had a tie. They both excelled with great documentation, examples, and very good reliability.”

Rotten Tomatoes

“The payload is well organized and simple to navigate. A dashboard to try the endpoints is a great addition. The reliability has also been very good.”

Weather Channel

“We found the console a valuable tool to work with.”


“Does everything well, and documents it clearly.”

All APIs reviewed and considered so far:

Airbnb, Associated Press, Bazaarvoice, BBC, Best Buy, BetterDoctor, BigCommerce, Box.net, Braintree, British Airways, Cars.com, CartoDB, CBS Sports, Close.io, Demandware, DocPlanner, Dropbox, Edmunds, Etsy, Evernote, Expensify, FedEx, FerrisTV, Financial Times, Flickr, Flightview, Foursquare, Freshbooks, Gawker, Giphy, Greenhouse, GrubHub, Harper Collins, Hearst, Hubspot, Hyatt, IMDB, Instagram, Intercom.io, JustWorks, Klarna, Last.FM, LeagueApps, Levi Strauss, Lowe’s, Lyft, Macy’s, MailChimp, MailGun, Mapquest, Mapsense.co, Marks & Spencer, Merriam-Webster Dictionary, Mixpanel, MLB, Advanced Media, NewsCred, Nielsen, Nordstrom, NY Times, Optimizely, PaidEasy, Pandora, Paypal, Pinterest, Priority Payment Systems, PubNub, QuietLogistics, Reddit, Redfin, Salesforce, SeatGeek, Shopping.com, Shopzilla, Shutterstock, SendGrid, Soundcloud, Soundhound, Spotify, Square, Stripe, StubHub, Trulia, Tumblr, Twitch.tv, United Airlines, UPS, USA Today, USPS, Vice, Vimeo, Washington Post, WeatherBug, WhitePages, Wikipedia, WordPress, Yahoo Weather, Yellow Pages, Yelp, Zappos, Zazzle, Zenefits, Zillow, Zoho

Note: This list is constantly being updated and revised. We are reviewing new APIs weekly.