API Rankings from API.expert

We have somehow come to the fourth week of June (and still one to go) and reached that time when we must discourse on the State of the APIs over the last seven days.

We launched API.expert earlier in the year as a simple way to provide everybody with insights into the API economy and the leading APIs in different categories in particular. The basic service is free and will remain free, but other, related services will be built on top of it, including your very own API.expert dashboards if you want them!

Each week, month and year we’ll look at the APIs we track in a variety of sectors for their quality using our patented CASC score (US Patent 10,644,962, if you fancy a little light bedtime reading) that allows you at a glance to see the performance of an API and compare it to other ones, as well as factors like uptime and availability.

If something is missing that you think should be here, don’t hesitate to drop us a line!

Now, onto what the past week tells us about the state of the world of APIs as we delve still further into June 2020.


API Performance Headlines

We look at over 200 APIs but pull all the metrics together to give you a general feeling for the service quality for an organization’s APIs in a particular category.

We do see that certain providers consistently vie for the top spot in their category including GitHub and Google with others doing less well such as Halifax and the NHS.


Top Performers:

Week Ending June 22, 2020

Category    Organization    CASC score
Corporate InfrastructureBox963
Covid-19The COVID Tracking Project934
Cryptocurrency ExchangesCoinpaprika917
PSD2 BanksNordea Bank988
Social NetworksGoogle975
UK Open Banking (Open Data)Bank of Ireland973
UK GovernmentGOV.UK988
US GovernmentDepartment of Justice978


A very volatile week this week, with seven out of the nine categories changing at the top:

  • GitHub replacing Box in Corporate Infrastructure
  • COVID-19 Finnhub API replacing The COVID Tracking Project in Covid-19
  • Coinpaprika replacing HitBTC in Cryptocurrency Exchanges
  • Nordea Bank replacing ABN AMRO Bank in PSD2 Banks
  • Google replacing Reddit in Social Networks
  • GOV.UK replacing Police.UK in UK Government
  • Department of Justice replacing the Federal Communications Commission in US Government

For the first time, the honors are split at the top and both the public and private sectors get a share of the glory with Nordea Bank in PSD2 Banks and GOV.UK in UK Government joint champions (no goal difference here) with the superb CASC score of 988.

A CASC score of over 900 is very good and one of 950 or more exceptional. Seven of the nine categories are headed by the organization with a CASC score of 950 or more this week. Sustaining a CASC score of >925 over several weeks is a good showing and congratulations to those organizations that achieved it.

Top Performers by Latency:

Week Ending June 22, 2020

Category    Organization    Median latency
Corporate InfrastructureMicrosoft Office220 ms
Covid-19CDC tools (Centers for Disease Control and Prevention)174 ms
Cryptocurrency ExchangesFTX207 ms
PSD2 BanksNordea Bank185 ms
SearchFacebook287 ms
Social NetworksGoogle55 ms
UK Open Banking (Open Data)HSBC82 ms
UK GovernmentPolice.UK75 ms
US GovernmentDepartment of Justice63 ms

In contrast to the CASC score, another stable week this week with no changes again to the top performers.

An important caveat: medians can be misleading! An API might have a fast median latency but produce many slow outliers. These won’t affect the median, but they mean that users can experience many unacceptably slow calls. So just being fast isn’t everything. You have to be reliable too if you want to have good APIs and get a high CASC score!

As so often, FTX tops the Cryptocurrency Exchange category and this week are sixth out of 18 overall with a CASC score of 867, placing them firmly in the Amber Zone. But it is still worth remembering that it’s no good just being fast if you are flakey, although being fast does help!

Worst Quality Across All Categories:

Week Ending June 22, 2020

CategoryOrganizationCASC score
Corporate InfrastructureNobody below 800! 
Covid-19Coronavirus COVID19 API (covid19api.com)698
Cryptocurrency ExchangesRadarRelay767
PSD2 BanksSquare (Sandbox)798
Social NetworksNobody below 800! 
UK GovernmentNHS563
UK Open Banking (Open Data)Halifax713
US GovernmentDepartment of Commerce581

Several changes this week. There is no loser award in Corporate Infrastructure! Also:

  • Coronavirus Data API (thevirustracker.com) replaces Coronavirus COVID19 API (covid19api.com) in Covid-19
  • Square (Sandbox) replaces BBVA in PSD2 Banks
  • Department of Commerce replaces the Bureau of Labor Statistics in US Government

The NHS takes the overall Loser Award with a disappointing Red Zone CASC score of 563.

Something of interest

Joint winners this week were Nordea Bank in PSD2 Banks and GOV.UK in UK Government, both with a near-perfect CASC score of 988. How do these practically flawless APIs compare with one another?

API.expert: State of the APIs, June 15-22, 2020 api ranking report

GOV.UK has slightly lower latency (174 ms) and zero outliers compared to Nordea Bank (185 ms and 0.02% outliers). GOV.UK was robbed, I hear you shout! But not so quick. The standard deviation also counts and a more consistent API, excluding outliers, is rewarded.

API.expert: State of the APIs, June 15-22, 2020

API.expert: State of the APIs, June 15-22, 2020

Interestingly, IBM Cloud is best for Nordea Bank and worst for GOV.UK. AWS is much better for GOV.UK than Azure and IBM Cloud is very similar, which might suggest these cloud locations are adjacent. Nordea Bank is more consistent across clouds. This is the ideal situation. It shouldn’t matter to the end-user which cloud a call is made from.

API.expert: State of the APIs, June 15-22, 2020

As we can see the difference between clouds for GOV.UK can be accounted for by our old friend, the DNS Lookup Time, which is 32 ms less for AWS than both Azure and IBM Cloud. This suggests that GOV.UK might be hosted by AWS, but either way, it shows that even a very, very good indeed API can improve by sorting out this kind of networking configuration issue that affects the user experience of a service. If GOV.UK sorted out its DNS issue, its CASC score would be even closer to perfect!

API.expert: State of the APIs, June 15-22, 2020

See you again in a week as we look once more at the State of the APIs as we get towards the end of June!