A URL slug is the human-readable part of a web address that identifies a specific page — the part after the domain name, like best-pizza-new-york in example.com/best-pizza-new-york. It looks like a small detail, but it affects both readability and, modestly, search visibility.
What a Slug Actually Is
A slug is derived from a page's title or main topic, converted into a URL-safe format: lowercase, spaces replaced with hyphens, and special characters stripped or converted. It exists to give both humans and search engines a readable clue about what the page contains, just from glancing at the address bar.
Why Shorter Beats Longer
A slug like best-pizza-new-york is generally preferred over the-absolute-best-pizza-restaurants-in-new-york-city. Search engines treat concise, keyword-relevant slugs as a small positive signal, and shorter slugs are simply easier for a human to read, remember, and share. Stripping filler words — "the," "a," "of," "in" — keeps the meaningful keywords front and center without unnecessary length.
Hyphens, Not Underscores
Hyphens are the standard separator for a reason: search engines have historically read a hyphen as a space between two distinct words, correctly parsing blue-widget as two searchable words. An underscore hasn't always been treated the same way, sometimes being read as joining the words into a single token instead — which is why hyphens became the de facto convention for slugs specifically.
Handling Accents and Special Characters
Since URLs are most reliably compatible using plain ASCII characters, accented letters are typically transliterated to their closest unaccented equivalent rather than percent-encoded or simply dropped — é becomes e, ñ becomes n. This keeps the slug both fully readable and safely compatible with every browser and system.
Generating a Slug Right Now
Paste any text into our free Slug Generator to get a clean, URL-friendly slug — choose a hyphen, underscore, or no separator, force lowercase, strip accents, cap the length without cutting mid-word, or batch-convert several lines at once.
FAQ
Does making a URL slug shorter actually help SEO? Shorter, descriptive slugs are generally considered a minor positive signal — they're easier for both users and search engines to read at a glance, and they avoid diluting keyword relevance with unnecessary filler words. It's a small factor rather than a major ranking lever on its own, but there's no real downside to keeping a slug concise and clear.
Should a URL slug include small words like "the," "a," and "of"? Most SEO guidance recommends stripping common filler words ("the," "a," "of," "and") from a slug, since they add length without adding meaning or searchable keywords. "best-pizza-new-york" reads just as clearly as "the-best-pizza-in-new-york" while being shorter and more keyword-dense.
What happens to accented characters like é or ñ when generating a slug? Since URLs are safest and most universally compatible using plain ASCII characters, accented letters are typically converted to their closest unaccented equivalent — é becomes e, ñ becomes n — rather than being percent-encoded or dropped entirely, which keeps the slug both readable and safely compatible everywhere.
Should I use hyphens or underscores in a slug? Hyphens are the standard, SEO-recommended choice. Search engines have historically treated a hyphen as a space between words, correctly reading "blue-widget" as two separate searchable words, while an underscore has at times been treated as joining the words into one — making hyphens the safer, more consistently supported option.