How many companies use Castle vs HTTP/3?

10 companies use Castle and 199,043 companies use HTTP/3 in our database. HTTP/3 is more widely adopted with 19904.3x more companies than Castle.

Can I get a list of companies using both Castle and HTTP/3?

Yes. AgentData tracks companies using both tools. Sign up free to access the full list with emails, tech stacks, and contacts via CSV or API.

HTTP/3 is used by 199,043companies — 19904.3x more than Castle (10).

10 use Castle199,043 use HTTP/3

	Castle	HTTP/3
Companies	10	199,043
Category	Analytics	Miscellaneous

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199,053 companies with emails, tech stacks, and contacts

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API access

GET /api/v1/tech?name=castle

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