Last updated July 2018
You might not know it’s called a URL, but you’ve probably seen one:
A uniform resource locator (URL) identifies a particular website, or a particular page or
feature within a website. Knowing how to interpret a URL is probably the best way to tell
whether a site is genuine or bogus.
Part 1: https
The first part of a URL is either http or https followed by a colon and two slashes. The latter
means that your communication with the site is protected against eavesdropping or interference
by your Internet provider, employer, someone else on the coffee shop Wi-Fi, and so on:
In 2018 we’re seeing the tipping point in a movement to protect all websites with https, and to
reflect this, browsers will soon no longer show this part of the URL. https will continue to be
indicated by a padlock icon, and plain old http will be indicated by a warning like ‘not
Note that the padlock doesn’t guarantee you’re on a genuine website. A bogus site can just as
easily use https. It’s no consolation knowing your message is private if the party you’re
sending it to isn’t who you think it is!
Part 2: the domain name
This is the important bit. The domain name continues until either a slash or the end of the
URL, whichever comes first. In our example, it’s en.wikipedia.org:
Computers actually read domain names from right to left, separating them at the dots. Usually,
the rightmost part – or two – indicates a country and/or type of organisation. These are called
- co.uk (commercial, UK)
- org (non-profit organisation)
- fr (France)
The part immediately to the left of the top-level domain is typically the name of the
Note: There are exceptions, like diy.com for do-it-yourself retailer B&Q.
Combining these parts, we have full domain names:
These are the best indicator of the legitimacy of a site. Remember, what matters is the
sections immediately before the first single slash (or end of the URL):
Fake or malicious sites might use a misspelling of a genuine domain:
- amaz0n.co.uk (contains a number zero where a letter ‘o’ should be)
- uicef.org (missing a letter)
- renualt.fr (two of the letters the wrong way round)
I wanted this guide to be really short, but it would be foolish of me not to explain a few
common caveats that make interpreting URLs harder in some cases.
Strange-looking but genuine subdomains
Sometimes, you’ll see subdomains like this:
Is this the real Apple website? Yes! Check the rightmost part of the domain. Apple has simply
chosen to use a server called secure-applednld; can you work out what it’s an abbreviation of?
On the other hand, a crafty bogus site might use a subdomain in this fashion:
Is this the real BBC website? No! At a glance, it looks like it might be an article in the
Health section, but there’s no slash after bbc.co.uk — the domain name continues, in this case
to the end of the address. It’s an elaborate one that in fact resolves to the server hosting
this site, martinedwards.co.uk. If I was so inclined, I could create a page at this URL,
mimicking the BBC but with some malicious software thrown in!
A domain name that looks suspicious at first might actually redirect you to a genuine site. For
example, if you’re on John Lewis’s mailing list, the emails you receive might contain links to
promotions that look like this:
This site is genuine. The domain list-manage.com is used by email marketing company MailChimp
to track which subscribers click which links in an email, to help the owner of the mailing list
(like John Lewis in this example) learn more about its customers.
Some companies use shorteners to make URLs that are more compact and
easier to communicate. These are really just redirects, but are increasingly common so deserve a
special mention. For example:
- https://t.co/Rk466PgT3r (this uses Twitter’s shortener) redirects to Gordon
Buchanan’s documentary about wolves on iPlayer
- https://aka.ms/wudiag (this uses Microsoft’s shortener) redirects to the much longer
URL of the Windows Update Troubleshooter, but is more convenient for a technician to dictate
to a customer over the phone
This isn’t a URL issue per se, but a link in an email or website may be made to look like a
URL that’s different from its actual destination. Try clicking this link and see where it takes
you (it’s harmless, just not what you expect):
You can usually reveal the true destination of a link by hovering your mouse over it or, on a
phone or tablet, long-pressing it (i.e. pressing and holding for a second or two).
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