URL Slug Generator: How It Works
A URL slug is the human-readable part of an address after the domain. It is a small ranking factor and a large usability one — and unlike most SEO decisions, it is expensive to change later, which makes getting it right the first time worth a minute of thought.
What a good slug looks like
| Poor | Better |
|---|---|
/p?id=4471&cat=12 | /espresso-machines/dual-boiler |
/Blog/2026/03/My_Post_Title!.php | /blog/choosing-a-dual-boiler |
/best-cheap-affordable-budget-coffee-machine-deals | /budget-espresso-machines |
The rules
- Lowercase only. Servers on Linux treat
/Pageand/pageas different URLs, which creates duplicate content from a capital letter. - Hyphens, not underscores. Google treats hyphens as word separators and underscores as joiners, so
red_shoescan be read as one token. - No spaces or special characters. They become percent-encoded and unreadable — a space becomes
%20. - Short. Three to five meaningful words is a good target. Every extra word dilutes the rest.
- Drop stop words where they add nothing:
/how-to-make-a-good-espressobecomes/make-good-espresso. - No dates unless the content is genuinely time-bound. A date makes evergreen content look stale and blocks painless updating.
Non-Latin characters
URLs technically support Unicode via percent-encoding, so a Tamil or Arabic slug is valid and displays correctly in modern browsers. The complication is that it becomes an unreadable encoded string when copied into plain-text contexts, and some older systems mangle it. Transliterating to ASCII is the safer default for international audiences, while native-script slugs can work well for a single-language site whose readers all share that script.
Changing a slug later
An existing URL with traffic and links has accumulated value that does not automatically transfer. If you must change it:
- Set a 301 permanent redirect from the old URL to the new one.
- Update every internal link to point directly at the new URL rather than through the redirect.
- Update the sitemap and resubmit it.
- Keep the redirect indefinitely — external links to the old URL will keep arriving for years.
Expect a temporary dip while search engines process the change. This is normal and usually resolves within weeks, but it is a real cost, which is why changing slugs for marginal keyword gains is rarely worth it.
Structure and depth
A shallow, logical hierarchy helps both users and crawlers: /category/subcategory/page is clear, while /a/b/c/d/e/page is not. Keep important pages within about three clicks of the homepage. Whether the folder structure matches your navigation matters less than whether it is consistent and predictable.
Trailing slashes and case
Pick one convention — with or without a trailing slash — and redirect the other. Do the same for uppercase. Both variants returning 200 creates duplicate URLs for every page on the site, which is one of the most common and least noticed technical issues in any audit.