A breakdown of the 5.6K+ companies running OpenAI API.
Top industries
Information technology and services3K+
Professional and business services752
Financial services410
Education and training324
Industrial and manufacturing229
Media and telecommunications123
Health and wellness111
Construction and building91
No industry recorded: 209
Company size
1–10813 (19%)
11–50723 (17%)
51–250923 (22%)
251–500384 (9%)
501–1,000277 (7%)
1,001–5,000508 (12%)
5,001–10,000179 (4%)
10,001+366 (9%)
Share of companies with a recorded size, by employees.
No size recorded: 1.4K+
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Frequently asked questions
About the OpenAI API data on this page.
How many companies use OpenAI API?
Firmable holds confirmed OpenAI API detections for 5,665 distinct companies, 2,692 of them confirmed in the last 90 days. A company is counted once however many of its properties run it.
Which companies use OpenAI API?
The Riverside Company, Centerbridge Partners, L.P. and Retool are among the most prominent in the current set.
What industries use OpenAI API?
Information technology and services, professional and business services and financial services lead the set, across 19 industries in total.
What size companies use OpenAI API?
Adoption concentrates in the 51-250 employee band, across the companies whose size is recorded.
Where are OpenAI API users based?
The United States, Canada, Australia and Singapore account for most detections, across 13 countries.
How current is this data?
2,692 companies were confirmed in the last 90 days. Last detection 13 October 2026.
