Slug Generator

What makes a good slug

A URL slug should be lowercase, use hyphens between words, contain only unreserved ASCII characters, and be short enough to read at a glance. Lowercase matters because path components are case-sensitive on most servers, so two casings of the same slug are two different URLs and therefore duplicate content. Hyphens matter because search engines treat them as word separators while underscores historically were not, so red-shoes reads as two words and red_shoes may read as one.

Accents and non-Latin scripts

Accented characters need transliteration rather than removal: café should become cafe, not caf. This is done by decomposing to Unicode NFD, which separates a base letter from its combining accent, then stripping the combining marks. Some characters need explicit mapping because decomposition does not cover them: the German sharp s to ss, the Nordic slashed o to o, the Polish crossed l to l.

For scripts with no Latin equivalent, you have a real choice. Percent-encoded Unicode slugs work in modern browsers and are more meaningful to native readers, though they look unreadable when copied as raw encoded text. Transliteration produces ASCII that is readable but sometimes awkward. Wikipedia uses native scripts successfully, which is reasonable evidence the approach is viable.

Stop words and length

Trimming articles and short prepositions keeps slugs tight, and there is no ranking penalty for their absence. Do not trim so aggressively that the slug stops making sense: how-to-tie-a-tie is better than tie-tie. Keeping the total under roughly 60 characters avoids truncation in search results and keeps the URL shareable.

Collisions and stability

Two different titles can produce the same slug, so the generator has to handle collisions, usually with a numeric suffix. More importantly, once a slug is published it should not change. Editing a title should not silently move the URL, because every existing link then breaks. If a slug must change, serve a 301 from the old one permanently.