What Is an "Aspirateur Web" (Web Copier) and How Do You Save a Website for Offline Browsing?

Updated

An "aspirateur web" (French for "web vacuum") is a web mirroring or web-copying utility: software that downloads a website from the internet into a local directory, recursively following links and pulling HTML pages, images, and other files so you can browse the copy offline in any browser. HTTrack Website Copier is a well-known open-source example; its own documentation describes it as an "easy-to-use website mirror utility" that rebuilds links relatively so the local site works in any browser, can mirror several sites together, and can update an existing mirror or resume an interrupted download. Use this approach when you need a browsable offline copy of a site you are permitted to copy; for a single article, your browser's "Save page" is simpler and cheaper.

What the tool actually does

A web copier works like a crawler with a filing cabinet attached:

  1. You give it a starting URL.
  2. It fetches that page, saves it locally, and extracts the links inside it.
  3. It follows those links (within the depth and filters you set), saving each file and rewriting links so they point to the local copies.
  4. The result is a folder you can open with any browser and navigate as if you were online.

HTTrack's description notes the robot is "fully configurable, with an integrated help," which matters because crawl scope is where most problems start.

Saving a site for offline browsing: the core steps

The exact menus differ by version and platform (HTTrack has a Windows front-end, WinHTTrack, and command-line versions), so treat these as the inputs and actions rather than a click-by-click script:

  • Project name and local folder — where the mirror will be stored. Estimate size first: a media-heavy site can run into gigabytes, and a full mirror takes far longer than saving one page.
  • Starting URL(s) — the page(s) where the crawl begins. You can add several sites to one project and jump between them offline.
  • Depth and limits — how many link levels to follow, and whether to stay on the same domain. Unlimited depth on a large site is the most common cause of runaway downloads.
  • Filters — include/exclude rules for file types or URL patterns (for example, skip large video files you don't need).
  • Start, then verify — when the crawl finishes, open the local index page in your browser and click through a few links, images, and subpages. HTTrack generates an index of locally available sites, which is a convenient starting point.

Full mirror vs. single page

Need Better choice Cost
Read one article or page later Browser "Save page" or print-to-PDF Seconds, small file
Browse a whole small site or documentation set offline Web copier with limited depth Minutes to hours, moderate storage
Archive a large site with media Web copier with filters and generous disk space Long runtime, large storage

Common failure points

  • Robots or login restrictions. Pages behind a login or disallowed by the site's robots rules may be skipped or blocked. Check that the pages you need actually downloaded rather than assuming success.
  • Dynamic content. Content loaded by scripts after the page loads may not be captured, leaving gaps in the offline copy.
  • Link rewriting quirks. Because links are rebuilt for local use, some absolute links or scripts can behave differently offline; test navigation rather than only opening the home page.
  • Interrupted runs. Long crawls get interrupted. HTTrack supports resuming an interrupted download and updating an existing mirror, so you can continue rather than starting over.

Practical notes

Mirror only sites you have the right to copy, and keep depth and filters tight on your first run to see how large the result grows. If a crawl stalls, lower the depth, add exclusion filters, and resume the existing project instead of creating a new one.