Websites are made up of web resources, or pages, located on a computer network. In order for users and search engines to access these pages, each web resource is given a Uniform Resource Locator (URL) that specifies where the resource is and how to retrieve it.
URLs can have values added to them. These values are called parameters. There are two main types of URL parameters:
- URL parameters for differentiating almost identical web pages.
- URL parameters for campaign tracking.
Parameters for web page differentiation
Websites will often have almost identical versions of the same web resource. For example, an eCommerce website selling ‘men’s shoes’ will likely have versions of the page with filtering applied according to colour, size, style and brand. In order to differentiate these very similar URLs, parameters are added.
URL parameters are the sections of a web address found after the question mark (?). Any word after this symbol can hold values. For example;
In this example, the question mark opens the URL to being assigned specific values. The first value category is ‘name’, for which the value is ‘nike’. The equals (=) symbol is necessary for assigning a corresponding value.
Multiple values can be assigned to a URL by separating them with an ampersand symbol (&). As you can see in the example above, the URL has an additional parameter category of ‘color’, for which the value is ‘purple’.
It is worth noting, however, that URL parameters can often cause problems for SEOs. Search engines will try to access and index every page it can on a website, and if there are dozens, if not hundreds, of almost identical URLs then the website is at risk of keyword cannibalisation.
In the case of the example above, if every possible filtering option for the men’s shoes category was a URL, this would result in potentially thousands of almost identical pages targeting ‘men’s shoes’ as a keyword. This would consequently confuse search engines for which page to show in the search results, thereby resulting in lower rankings. It would also result in crawl budget being used unnecessarily, which could affect how often areas of the site are visited by search engines and indexed.
As such, it is important that URLs with parameters applied are canonicalised to a primary URL. Moreover, pages with parameter URLs should have a no-index tag implemented to indicate that the page should not be indexed by search engines. A website should also include a robots.txt directive to block search engine bots from crawling and indexing any parameter URLs.
Parameters for campaign tracking
As mentioned above, URL parameters can also be used for tracking purposes. These are known as Urchin Tracking Module parameters (UTM).
A website owner may wish to track how users are landing on certain pages to see how different channels and campaigns are performing. They can do so by applying a parameter to the URL. There are five parameters that can be added to a URL for tracking:
The method through which your marketing arrived at the user. Examples include ’email’ and ‘social’, among others.
The specific site that the user arrived on your site from. For example, if the medium is “social” and you ran an Instagram campaign, the source might be “Instagram”.
The name of the marketing campaign itself, ie – “Instagram Gardening Product Campaign 2020”
Typically used when testing different promotions in tandem. Different content might be used as part of the same campaign, so you would add a content attribute to conduct an A/B test.
This tag is used to identify specific keywords within paid search campaigns, outside of Google. If you’re advertising on Google, then it’s possible (and recommended) to set up auto-tagging.
Although the above may sound technical, it can be implemented very easily with the aid of Google’s URL Builder.
Below is an example of a URL with tracking parameters applied:
We can break this example down:
This parameter is defining the source of the user as ‘facebook’. Spaces cannot be used in a URL, and as such the symbols ‘%20’ are used.
Here the medium is defined as ‘social’, as it is a social network.
The campaign is defined as ‘product launch’.
The content parameter is defined as ‘top CTA button’, which is a reference to the specific link on the campaign that users have clicked on. This is to help identify the optimal CTA placement for future campaigns.
These parameters can then be tracked in Google Analytics and used for further analysis. For further information on tracking parameter URLs in Analytics, check out Sean’s beginner’s guide to GA.
Gaining an understanding of URL parameters is a useful exercise for anyone working with websites on a day-to-day basis. Understanding how parameters can help the user, as well as potentially cause cannibalisation issues, is key in SEO. Similarly, paid media campaigns rely on accurate tracking and being able to get granular in crafting your own campaigns is a great skill to have.