GlossarySEO
What are URL parameters, and how do they affect SEO?
Also called: query parameters, query strings, query string parameters
Definition
URL parameters are the key=value pairs after a ? in a URL, like ?ref=twitter or ?sort=price. Each unique combination is a separate URL to search engines, even when the content barely changes.
URL parameters, explained
Parameters do three kinds of work. Tracking parameters (utm_source, ref, gclid) record where a visitor came from and don't change the content. Presentation parameters (sort, view, lang in some setups) reorder or restyle the same content. Content parameters (page, category, q) change what's shown. Search engines can't tell these apart without crawling.
Google's URL structure guidance says to shorten URLs by trimming parameters that don't change the content, to use = between key and value and & between pairs, and to avoid session IDs in URLs in favor of cookies. Its ecommerce guide adds that Google may not realize two URLs return the same page until after it has fetched both, which wastes crawling. Search Console's old URL Parameters tool was retired in 2022, so you manage this on your site now.
The practical setup: never use tracking parameters in your own internal links. Give every page a self-referencing canonical without parameters, so shared links like ?utm_source=newsletter consolidate to the clean URL. Keep parameter URLs out of the sitemap. For sort and filter parameters that multiply, block crawling in robots.txt or avoid generating crawlable links to them. Keep ?page= crawlable when it's pagination.
Keep parameter order consistent, and don't repeat keys, so the same state always produces the same URL.
Why it matters for founders
Launch posts, newsletters and directory listings all add tracking parameters to your links. Without canonicals, Google may index ?ref=producthunt versions of your homepage instead of the clean one.
Example
Search Console shows /?ref=launch-badge indexed as a separate page. You confirm the homepage has a self-canonical to https://example.com/, and the parameter version moves to "Alternate page with proper canonical tag".
Common mistakes
- Using UTM-tagged links inside your own site.
- No canonical on pages that receive tracking parameters.
- Listing parameter URLs in the sitemap.
- Session IDs in URLs.
Sources
- Google Search Central: URL structure best practices
- Google Search Central: Designing a URL structure for ecommerce sites
Checked
Related terms
- CanonicalizationCanonicalization is how a search engine picks one representative URL from a group of pages with the same or very similar content, and shows only that one in results.
- Faceted navigationFaceted navigation lets users filter a list by attributes like category, price or rating. Each filter combination can create a new URL, which can multiply into far more crawlable URLs than real pages.
- UTM parametersUTM parameters are tags added to a URL, like
?utm_source=newsletter&utm_medium=email&utm_campaign=launch, that tell analytics tools where a visit came from. - Canonical tagA canonical tag is a line in a page's HTML,
<link rel="canonical" href="…">, that tells search engines which URL is the main version when several URLs show the same or very similar content.