Slugify

What a slug is

A slug is the human-readable, URL-safe portion of a URL — /blog/my-post-title has slug my-post-title. It identifies the resource and contributes to SEO (Google reads slug words). It must be ASCII-safe, lowercase by convention, and use a separator that browsers won't mangle (- wins).

The transformation from arbitrary text to slug involves three steps:

1. Transliterate non-ASCII characters into ASCII equivalents (café → cafe, Tiếng Việt → tieng-viet, Schöner Tag → schoner-tag).
2. Normalize whitespace and punctuation to your chosen separator.
3. Lowercase (almost universally — search engines case-fold URLs anyway).

This tool handles all three. Pick the right locale for the input text so transliteration uses the right rules — Vietnamese ư is u, not w; German ü is ue traditionally but u is more common in modern URLs.

Why hyphen over underscore

Google indexes hyphens as word separators (my-blog-post = three words) but underscores as joiners (my_blog_post = one word). For SEO, always use hyphen in URL slugs. Underscores are fine for filenames or identifiers, not URLs.

Diacritics: strip or transliterate

Two schools of thought:

• Strip: Café → caf. Loses the é entirely. Wrong — drops a letter.
• Transliterate: Café → cafe. Keeps the letter, drops the diacritic. Right.

This tool transliterates. For Vietnamese, the locale-specific map turns đ → d (the standard slugify library handles the rest of Vietnamese diacritics via NFD normalization).

Length and SEO

Most SEO guidance lands on 3–5 words for the slug (~30–60 characters). Longer slugs aren't penalized but are uglier in social shares. Don't pad with stop words ("the", "a", "an") — they add length without meaning.

Use cases

• Generating URL paths for CMS-driven content
• Building filenames from human titles
• Creating user-friendly IDs from arbitrary input
• Bulk-generating slugs for an import batch (use the Bulk tab)

Privacy

All processing in your browser via slugify. No network requests.

Related

• Text Case Converter — change to lowercase before slugifying, or invert order.
• URL Encoder — for query parameters and full URL composition.

Hyphen or underscore?

Hyphen. Google indexes hyphens as word separators and underscores as joiners — for SEO you almost always want word separation.

Should slugs keep diacritics?

Tech-wise yes (/café), SEO-wise no (/cafe) — most English audiences and most non-Latin browsers will see encoded %C3%A9 instead of é. Strip diacritics for portability.

What's the max slug length?

No hard limit, but ~60 characters is the practical ceiling for SEO (Google truncates display in SERPs after ~50–60). Stick to 3–5 meaningful words.

How does Vietnamese transliteration work here?

The underlying library transliterates standard Vietnamese diacritics via NFD normalization (ế → e, ư → u). We add a small map for special cases (đ → d) that NFD doesn't handle by default.

Slug for non-Latin scripts (Chinese, Japanese, Arabic)?

Pinyin/romaji transliteration is possible but not enabled here by default. For Chinese: use a pinyin library before slugifying. For Japanese: romaji conversion. For Arabic: transliteration is debatable — many sites just keep the original characters URL-encoded.