A breakdown of the 399 companies running Windows API.
Top industries
Information technology and services218
Industrial and manufacturing48
Professional and business services45
Financial services17
Construction and building11
Education and training11
Media and telecommunications9
Art, sports and recreation8
No industry recorded: 11
Company size
1–1020 (5%)
11–5049 (13%)
51–25078 (21%)
251–50042 (11%)
501–1,00030 (8%)
1,001–5,00060 (16%)
5,001–10,00016 (4%)
10,001+74 (20%)
Share of companies with a recorded size, by employees.
No size recorded: 30
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Frequently asked questions
About the Windows API data on this page.
How many companies use Windows API?
Firmable holds confirmed Windows API detections for 399 distinct companies, 48 of them confirmed in the last 90 days. A company is counted once however many of its properties run it.
Which companies use Windows API?
Iru, Motive Partners and CLOUDSUFI are among the most prominent in the current set.
What industries use Windows API?
Information technology and services, industrial and manufacturing and professional and business services lead the set, across 17 industries in total.
What size companies use Windows API?
Adoption concentrates in the 51-250 employee band, across the companies whose size is recorded.
Where are Windows API users based?
The United States, Australia, Canada and Singapore account for most detections, across 13 countries.
How current is this data?
48 companies were confirmed in the last 90 days. Last detection 10 September 2026.
