link hygiene notebook/link-shorteners-explained/
Short links

Link Shorteners: What They Do and When to Be Careful

How a shortener works

URL shortening is a technique that makes a web address much shorter while still leading to the required page. The shortening service stores the long address against a short code. When someone visits the short link, the service looks up the code and sends the browser on to the long address using an HTTP redirect.

That single step is the whole trick, and it explains both why short links are handy and why they deserve a moment's thought.

Why people use them

The downsides

A short link hides its destination. You cannot tell from the code whether it leads to a news article, a file download or a page pretending to be your bank. Because the owner can sometimes change the destination later, a link that was safe last month may not be safe today.

Short links also depend on the shortening service staying alive. If the service closes, every link it issued can stop working at once, which is a form of link rot.

Expanding a link before you click

  1. Some shorteners show a preview page if you add a particular character to the end of the link; check the service's own help pages.
  2. On a computer, hovering over a link usually shows the address in the corner of the browser, though only the short form.
  3. Link-expanding tools take a short link and report where it finally lands without opening the page in your browser.
  4. If the message came from someone you know but feels unusual, ask them through a different channel before clicking.

If you share short links yourself

Rule of thumb

Short links are fine for low-stakes sharing. For anything that asks you to log in, pay or download, go to the site directly by typing its address or using your own bookmark rather than following a short link.

Last checked 2026-11-09