$ snippet slugify

Slugify a string for URLs

Turn 'Crème Brûlée & Friends!' into 'creme-brulee-and-friends' — strips accents, handles symbols, trims dashes.

JavaScript

const SPECIAL = { "ß": "ss", "æ": "ae", "œ": "oe", "ø": "o", "ł": "l", "đ": "d", "þ": "th" };

function slugify(str, { maxLength = 80 } = {}) {
  return str
    .toLowerCase()
    .replace(/[ßæœøłđþ]/g, (c) => SPECIAL[c])
    .normalize("NFKD")                    // split accented chars into base + mark
    .replace(/[\u0300-\u036f]/g, "")      // drop the marks
    .replace(/&/g, " and ")
    .replace(/[^a-z0-9\s-]/g, "")         // remove anything else
    .trim()
    .replace(/[\s_-]+/g, "-")             // collapse whitespace/dashes
    .replace(/^-+|-+$/g, "")
    .slice(0, maxLength)
    .replace(/-+$/, "");
}

How it works

normalize("NFKD") decomposes é into e + a combining accent, which the next line removes — that single trick handles most Latin-script languages. Everything not alphanumeric is dropped, whitespace becomes one dash, and edge dashes are trimmed so you never get -hello-.

Gotchas

Non-Latin scripts (Cyrillic, CJK, Arabic) are removed entirely by this version. If you need them, allow \p{L}\p{N} with the u flag instead of a-zA-Z0-9, and keep in mind browsers percent-encode them in URLs.
Slugs are not unique. Append an id or a counter when storing them.
Some letters are not decomposable by NFKD (ß ø ł æ) — that's what the SPECIAL map is for. Extend it for languages you serve.

Try it

Result

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