VendorStacks

Companies using Customer.io

17 companies in the VendorStacks index name Customer.io as part of their email stack in their public web presence. Every match carries the quoted source row it was extracted from — no inference, no fingerprint guessing.

Email

Sample of companies using Customer.io

CompanyUsed for
hubstaff.comEmail
growthspace.comEmail
getharvest.comEmail
vantage.coEmail
safetyculture.comEmail
respond.ioEmail
magicplan.appEmail
inato.comEmail
fountain.comEmail
validity.comEmail

Showing 10 of 17. The full list — with evidence, source URLs and refresh timestamps — comes back from one API call.

curl "https://vendorradar-production.up.railway.app
/v1/prospect?vendor=Customer.io" \
  -H "Authorization: Bearer vr_live_…"
Get an API key — 25 free creditsAPI reference

Commonly appears alongside

Vendors that most often show up in the same stacks as Customer.io.

AWS 15OpenAI 12Stripe 11Twilio 10Salesforce 9Snowflake 9

How this is collected

VendorStacks runs a multi-source extraction pipeline over a company's public web presence: crawling, rendering JavaScript pages and PDFs, and matching a deterministic vendor taxonomy against what the company itself publishes. Nothing is inferred from tracking pixels or guessed from job posts — if we say a company uses Customer.io, we can show you the sentence that says so. How it works →

Most recent refresh in this set: 2026-07-27.