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Prefetch & Preconnect Exporter

Export all resource hints of a page: prefetch, preconnect, dns-prefetch, prerender and speculation rules. See what the site warms up in advance.

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What is the Prefetch & Preconnect Exporter?

Resource hints help a browser get ready before it needs something. preconnect and dns-prefetch open connections to other servers early. prefetch downloads files for the next page. Speculation rules can even load whole pages in advance.

This tool collects all of these hints from the HTML, HTTP headers and speculation rules scripts, and puts them in one table you can export. It is a quick way to review a site's speed setup.

How to use it

  1. Paste the address of the page.
  2. Press Get resource hints.
  3. Review preconnect, dns-prefetch, prefetch and speculation rules.
  4. Export the list with CSV.

Why people like this tool

All hint types

prefetch, preconnect, dns-prefetch, prerender and next.

Speculation rules

Reads <script type="speculationrules"> JSON.

Headers included

Hints sent as HTTP Link headers are listed.

Counts by type

See at a glance how many of each hint the page uses.

How it works, in one picture

Infographic: how to use the Prefetch & Preconnect Exporter in 4 easy steps: Paste the link, Run the tool, Check the result and Save your file. You get: All hint types, Speculation rules, Headers included and Counts by type.

Frequently asked questions

preconnect or dns-prefetch?
preconnect does more (DNS, connection and TLS) and is best for 2 to 4 key servers. dns-prefetch is lighter and fine for more servers.
What are speculation rules?
A newer Chrome feature where a site lists pages to prefetch or prerender, so clicks feel instant.
Can too many hints hurt?
Yes. Too many preconnects waste the browser's time and data. Keep only the ones that matter.

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