Public signal checker
Third-Party Services Checker
This checker makes external dependencies easier to discuss by grouping visible resource hosts into practical categories.
The check uses public live signals and does not make a security, malware, fraud or legal verdict.
Run a public signal check
- HTTP
- DNS
- TLS
- RDAP
- Archive
What this checker analyzes
- Script, stylesheet and linked resource hosts that are not first-party domains.
- Categories such as analytics, advertising, CDN, fonts, media embeds, payment, chat and anti-spam.
- First-party resource hosts for comparison.
Why it matters
- Third-party services can influence privacy, performance, uptime and vendor risk.
- A grouped map is easier for website owners and agencies to review than a raw list of URLs.
What the results mean
- Known categories are based on common public domains.
- Unknown third-party means the host did not match a known category and may need manual review.
- First-party means the host belongs to the checked domain or one of its subdomains.
Limits of this check
- Resource URLs hidden behind JavaScript execution may be missed.
- A domain category does not prove what data is processed.
- The map is not a vendor contract or legal assessment.
What should also be reviewed manually?
Review notable values in the context of the actual website, its subpages and connected services. A homepage check cannot prove the complete configuration, legal position or security posture.
FAQ
Are third-party services always bad?
No. They are common. The value is knowing which services exist and whether they are expected.