What is a URL Slug?
A URL slug is the part of a web address that comes after the domain name and identifies a specific page in a readable way. For example, in example.com/blog/my-first-post, the slug is my-first-post. Unlike auto-generated IDs or query strings, slugs are designed to be human-readable, descriptive, and easy to share. They originated in the publishing industry where “slug” referred to a short label for an article in production.
Why Slugs Matter for SEO
Clean, descriptive URLs are a confirmed ranking signal for search engines. Well-crafted slugs improve your site’s SEO in several ways:
- Keyword relevance — Including target keywords in the slug helps search engines understand the page’s topic.
- Click-through rate — Users are more likely to click on a readable URL in search results than a string of random characters.
- Shareability — Clean URLs look trustworthy when shared on social media, email, and messaging apps.
- Link anchor text — When someone pastes a raw URL as a link, the slug itself acts as descriptive anchor text.
Best Practices for URL Slugs
Keep it short
Aim for 3-5 words. Remove filler words like "a", "the", "and", "is" unless they change the meaning.
Use hyphens as separators
Google treats hyphens as word separators. Avoid underscores, spaces, or special characters in URLs.
Stick to lowercase
URLs are case-sensitive on many servers. Using all lowercase avoids duplicate content issues and broken links.
Include target keywords
Put your primary keyword near the beginning of the slug. Avoid keyword stuffing — one or two keywords is enough.
Avoid special characters
Stick to letters, numbers, and hyphens. Transliterate accented characters to their ASCII equivalents.
Make it timeless
Avoid dates or version numbers in slugs unless essential. Evergreen slugs let you update content without changing URLs.
Examples
| Original Title | URL Slug |
|---|---|
| Hello World! | hello-world |
| My Blog Post: A Journey | my-blog-post-a-journey |
| Café & Résumé | cafe-resume |
| 100% Free & Open Source | 100-free-open-source |
| What is a URL Slug? | what-is-a-url-slug |
| Über cool für dich! | uber-cool-fur-dich |
Frequently Asked Questions
A URL slug is the human-readable part of a web address that identifies a specific page. For example, in the URL "example.com/blog/my-first-post", the slug is "my-first-post". Slugs are designed to be easy to read, type, and share while remaining compatible with web browsers.
Search engines use URLs as a ranking signal. Clean, descriptive slugs that include relevant keywords help search engines understand your page content, improve click-through rates in search results, and make URLs more shareable on social media. Short, keyword-rich slugs consistently outperform long, auto-generated ones.
Best practice is to limit slugs to lowercase letters (a-z), numbers (0-9), and hyphens (-) as word separators. While underscores and dots are technically valid, hyphens are preferred because Google treats hyphens as word separators but treats underscores as joiners.
Hyphens are strongly recommended. Google officially treats hyphens as word separators (so "web-design" is read as "web" + "design"), while underscores join words together ("web_design" is read as "webdesign"). Most SEO experts and major platforms default to hyphens.
Keep slugs under 60-70 characters for best results. Shorter slugs are easier to read, share, and remember. Focus on 3-5 keywords that describe the page content. Remove stop words (a, the, and, is, etc.) when they are not essential to meaning.
Transliteration replaces accented and special Unicode characters with their closest ASCII equivalents. For example, é becomes e, ñ becomes n, ü becomes u, and ß becomes ss. This ensures your slugs are compatible with all browsers and systems without percent-encoding.
No. All slug generation happens entirely in your browser using JavaScript. Your text never leaves your device — nothing is uploaded, stored, or logged. You can verify this by disconnecting from the internet and using the tool offline.
Absolutely. While the tool is designed for URL slugs, the same sanitization logic works perfectly for generating clean filenames, database keys, CSS class names, and any other identifier that needs to be safe and human-readable. Use underscores or dots as the separator depending on your convention.