What is URL slug?
A URL slug is the last, human-readable part of a URL path that identifies a specific page, such as waterproof-boots in /guides/waterproof-boots/.
A URL slug is the part of a URL that identifies one specific page in readable words. In https://www.example.com/guides/waterproof-hiking-boots/, the slug is waterproof-hiking-boots; /guides/ is the folder it sits in. Most CMSs generate the slug from the page title, and you can usually edit it before publishing.
Why slugs matter
Google’s URL structure guidelines recommend simple, descriptive URLs that use words rather than long ID numbers. The ranking weight of words in a URL is small, but a good slug pays off in other ways:
- Clicks and trust. URLs appear in search results, link previews, chat messages and printed material. A readable slug tells people what to expect before they click.
- Anchor text by default. When people paste a bare URL as a link, the slug becomes the visible text.
- Stability. A clean, timeless slug rarely needs to change, so you avoid redirects and lost signals later.
Good and bad slugs
| Avoid | Prefer | Why |
|---|---|---|
/p?id=48213 | /waterproof-hiking-boots/ | Descriptive words beat opaque IDs |
/how-to-make-sure-your-hiking-boots-are-really-waterproof-in-2026/ | /waterproof-hiking-boots/ | Shorter, and no year to update |
/Waterproof_Hiking_Boots | /waterproof-hiking-boots/ | Lowercase, and hyphens rather than underscores separate words |
/boots-boots-hiking-boots-cheap/ | /cheap-hiking-boots/ | No stuffing |
Non-English slugs are fine. Google supports UTF-8 characters in URLs; browsers display them readably while the URL itself is percent-encoded, for example /chaussures-randonnée/ becoming /chaussures-randonn%C3%A9e/. Be consistent: pick one form and link to it everywhere.
Rules of thumb
- Use the page’s main topic in three to five words where possible.
- Drop filler words only when the slug stays readable; “how-to-tie-shoes” is better than “tie-shoes”.
- Keep everything lowercase. Paths are case-sensitive on most servers, so
/Bootsand/bootscan be two different URLs. - Choose a trailing-slash convention and stick to it, redirecting the other form.
- Leave dates and numbers out of evergreen content.
Changing a slug
Changing the slug of a published page creates a new URL. If you must change it, add a 301 redirect from the old URL, update internal links and your sitemap, and point the canonical tag to the new address. Do it rarely: every change costs a little time while search engines process the move, and every redirect is a dependency you have to maintain.
Common mistakes
Letting the CMS create slugs from long draft titles, publishing duplicates with “-2” appended, switching slugs to chase a new keyword without redirects, and mixing uppercase and lowercase variants in internal links.
How to check
The On-Page SEO Checker reviews the page URL together with the title, H1 and description, so you can see whether all of them describe the same topic. The slug is one small piece of on-page SEO; get it right once and leave it alone.
Frequently asked questions
How long should a URL slug be?
There is no official limit for SEO, but short is better: three to five meaningful words usually describe a page well and stay readable in search results and shared links.
Should I use hyphens or underscores in slugs?
Use hyphens. Google recommends hyphens to separate words in URLs; underscores are less reliably treated as word separators.
Will changing a URL slug hurt rankings?
It can cause a temporary dip while Google processes the change. Add a 301 redirect from the old URL and update internal links to keep the impact small, and avoid changing slugs without a good reason.