Performance
PerformanceMedium

Third-Party Scripts

Checks the count and impact of third-party scripts (analytics, chat, ads).

What this check measures

We count <script> tags loading from non-first-party domains. 5+ third-party scripts on a page cost real performance — each adds to network, parse, and execute time.

Why it matters

Third-party scripts are the #1 performance debt on most sites. Every chat widget, analytics, ad tracker blocks main thread. They also leak data and degrade CSP posture.

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How our audit detects it

Parse <script src> tags, group by domain. Count non-first-party origins.

Typical findings

  • error_outlineAnalytics + 2 chat widgets + error tracker + 3 ad scripts = 7 third parties.
  • error_outlineSame tag manager contains 15 scripts loaded serially.

How to fix

Audit: which third parties are actually used? Remove unused ones. Consolidate (e.g., use one analytics). Load all with async or defer. Consider a tag manager only if you use 5+ scripts.

Frequently asked questions

Can analytics be synchronous?expand_more
Never. Always async — measurement data is not worth blocking the main thread.

Want this checked on your site?

Pantra runs the full audit (SEO, Security, GEO, Performance, Schema, Technical, Images) in 10 seconds and generates stack-specific fix prompts.

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