What it reads
The scripts and stylesheets your home page loads from public library hosts, such as cdnjs, jsDelivr and unpkg, and how many carry an integrity hash.
Check 52 of 54 · Supply chain
Subresource Integrity, explained.
Whether code your site loads from public library hosts is checked against tampering.
Engine 1.57.0, read 25 October 2026
Free checkScoredReliability: Moderate
Whose code runs on your website?
What the check does, and where it stops.
Why it matters
If a public library host is compromised, an integrity check is what stops an altered file running on your site.
What a failure looks like
A failure is a finding in your result. The check is scored, so it can lower your score, and the Full Report gives every finding its severity and a fix. If the check cannot finish, it is recorded as unknown: it carries no penalty, and it is never a pass.
Where its limits are
Home page as served. Other outside code is listed under third-party code and not graded here. That includes tag managers, and your own asset domains under another name.
ReliabilityModerate: confirm before acting
Check 52 is one of 4 in Supply chain. See it in its row on the scanner page, beside the rest of Supply chain.
See how your domain does.
The free check includes this one and takes about 30 seconds. No account. Nothing to install.