How many companies use Castle vs Site Kit?

10 companies use Castle and 11,730 companies use Site Kit in our database. Site Kit is more widely adopted with 1173.0x more companies than Castle.

Can I get a list of companies using both Castle and Site Kit?

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.

Site Kit is used by 11,730companies — 1173.0x more than Castle (10).

10 use Castle11,730 use Site Kit

	Castle	Site Kit
Companies	10	11,730
Category	Analytics	Analytics

Get the full comparison

11,740 companies with emails, tech stacks, and contacts

1,000 lookups · API access · CSV exports

API access

GET /api/v1/tech?name=castle

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