A URL slug is the part of a URL that comes after the domain name (and any subdirectory path) that identifies a specific page on a website. For example, in the URL example.com/blog/what-is-seo, the slug is what-is-seo. Slugs are an important — though minor — on-page SEO element because they contribute to URL readability, provide a keyword signal to search engines, and appear in search results under the page title where users can read them before clicking.

Best Practices for SEO-Friendly Slugs

An effective URL slug should be short and descriptive — ideally 3–5 words that clearly convey the page's topic. Use hyphens to separate words (not underscores — Google treats hyphens as word separators but underscores as word joiners). Include the primary target keyword in the slug. Avoid stop words (a, the, is, and, of) unless they are semantically important. Avoid dynamic parameters, numbers, or dates unless the page is inherently date-specific (like news articles). Once a slug is set and the page is live, changing it requires setting up a 301 redirect from the old URL to the new one to preserve link equity and avoid broken links.

URL stability: Changing slugs on established pages can cause temporary ranking drops and requires careful redirect implementation. Plan slugs thoughtfully before publishing pages to avoid the need for future changes.

Why It Matters for SEO

While slugs are a minor ranking factor, they influence several aspects of SEO performance:

  • Keywords in URLs provide a relevance signal — though a weak one compared to title and content
  • Clean, readable URLs improve click-through rates as users see them in search results and breadcrumbs
  • Short URLs are easier to share, remember, and link to
  • Well-structured URLs help search engines understand site architecture
  • Changing URLs on live pages risks losing link equity if redirects aren't properly configured