WordPress Permalinks and Slugs: Best Practices

WordPress supports three kinds of permalinks: plain, pretty and "almost pretty". Plain permalinks look like ?p=123, work on every server and are the default on a new install, but WordPress itself calls them not user-friendly. Pretty permalinks contain words such as the post name; "almost pretty" permalinks are the same with /index.php/ in front. Both need a web server configured for them, which your host normally does. Under Settings → Permalinks you choose one of six common settings:

A custom structure is built from structure tags: %year%, %monthnum%, %day%, %hour%, %minute%, %second%, %post_id%, %postname%, %category% and %author%. The documentation recommends ending the structure with %post_id% or %postname%, so that each URL points to exactly one post.

Use Post name unless you have a reason not to. It matches Google's advice to use simple, descriptive words rather than long ID numbers, and it keeps URLs short. Our URL slug length guide explains why short slugs are easier to read, share and maintain.

Use dates only when the date is part of the content. A date in the URL makes an evergreen tutorial look old the day the year changes, and you cannot remove the date later without changing every URL.

Be careful with %category%. It adds context, but a post in several categories gets the category that comes first alphabetically, and moving a post to another category changes its URL. The category and tag bases (category and tag by default) can be renamed in the optional settings, but not removed.

Avoid Plain and Numeric for public sites. Neither tells a reader or a search engine what the page is about.

When you save a post without typing a slug, WordPress runs the title through sanitize_title(). In the save context that function first calls remove_accents() and then the sanitize_title filter, whose default handler is sanitize_title_with_dashes(). That function:

1. removes HTML tags and stray % signs that are not part of an encoded byte;
2. lowercases the text and percent-encodes every non-ASCII character in lowercase hex, keeping at most 200 encoded characters;
3. turns non-breaking spaces, en and em dashes and / into hyphens, and strips curly quotes, the copyright sign, the ellipsis and similar symbols;
4. turns periods into hyphens and deletes everything except a–z, 0–9, spaces, _, - and the % of encoded bytes;
5. turns whitespace into hyphens, collapses repeated hyphens and trims hyphens from both ends.

Here is what that means for real titles, next to the default output of our generator:

The first two rows are the examples from the WordPress documentation. The differences are small but visible: WordPress deletes & and % instead of spelling them out, and it glues digits to the preceding word when only punctuation separated them. Neither is wrong, but if you care about the exact wording, type the slug yourself.

WordPress also keeps every small word. If you prefer 10-tips-tricks-faster-pages, remove the stop words in the slug field, or let our generator do it with the Remove stop words option.

sanitize_title_with_dashes() does not transliterate. Chinese, Japanese, Cyrillic and other non-Latin characters are kept and stored percent-encoded:

Browsers decode these bytes and show 重庆火锅攻略 in the address bar, so the URL looks fine to you. But when the link is copied into an email, a chat app or a spreadsheet, it often appears in its encoded form, 54 characters long for six Chinese characters. Each Chinese character takes 3 bytes in UTF-8, and each byte becomes three characters such as %e9.

The 200-character limit matters too. Because each Chinese character costs 9 encoded characters, a title made only of Chinese characters keeps at most 22 of them; the rest of the title is silently cut off.

You have three choices for a Chinese-language WordPress site:

1. Keep the Chinese slug. It is valid, Google supports it, and it reads well in the address bar. Keep titles short so the 22-character cap does not cut them.
2. Use pinyin. Our URL slug generator converts Chinese to toneless pinyin: 重庆火锅攻略 becomes chong-qing-huo-guo-gong-lve. Copy it into the slug field.
3. Use an English slug, such as chongqing-hot-pot-guide, if your audience also searches in English.

Our Chinese URL slug guide compares the three options in depth, including the polyphone problems of automatic pinyin. For accented Latin titles, WordPress's remove_accents() step already removes most accents; see how to transliterate slugs for the details of each language.

WordPress keeps post slugs unique. If sample-post already exists for the same post type, wp_unique_post_slug() appends a number and tries sample-post-2, then sample-post-3, and so on. Drafts and pending posts are not checked until they are published, so a duplicate can appear at the moment you click Publish.

Purely numeric slugs get special treatment, because they could clash with date archives. With the structure /%year%/%postname%/, a slug of 5 would look like the archive for May, so WordPress adds a suffix. Words make better slugs anyway.

When you see -2 at the end of a new URL, check for an old draft, a trashed post or an attachment with the same name, and fix the slug before you share the link.

Posts: when you change the slug of a published post, WordPress stores the old slug in the post's _wp_old_slug meta field. If someone later requests the old URL and it returns a 404, wp_old_slug_redirect() looks up the old slug and redirects with a 301 to the current permalink. If no old slug matches, it also tries the post's old publication date, so date-based URLs survive a date change.

Pages: wp_old_slug_redirect() does not redirect hierarchical post types, so pages are not covered. If you rename a page, add a 301 redirect yourself, in your server configuration or with a redirect plugin.

Changing the whole permalink structure changes every URL on the site at once. Do not rely on WordPress to catch all of them. Treat it as a migration: export the old URLs, map each one to its new URL, and generate the rules with our 301 redirect generator. Our bulk URL change guide walks through the whole process, including testing. In .htaccess, place your rules above the # BEGIN WordPress block so WordPress does not answer first.

[ ] Permalink structure chosen before launch (Post name for most sites)
[ ] Custom structures end with %postname% or %post_id%
[ ] No dates in URLs of evergreen content
[ ] Slug typed or checked by hand for important posts
[ ] Chinese titles: Chinese slug kept short, or pinyin/English slug entered
[ ] No unexpected -2 suffix; no purely numeric slugs
[ ] Renamed pages have a manual 301 redirect
[ ] Structure change treated as a migration: map, rules, tests
[ ] Redirect rules placed above # BEGIN WordPress in .htaccess

Paste a title into the URL slug generator to get a clean slug with & spelled out, optional stop-word removal and pinyin for Chinese, then copy it into the slug field in WordPress. For a whole export of post titles, the bulk CSV slug generator creates every slug in one pass and can make duplicates unique. Before you publish, the slug checker flags uppercase letters, underscores and other problems.

• WordPress Documentation: Customize permalinks
• WordPress Code Reference: sanitize_title()
• WordPress Code Reference: sanitize_title_with_dashes()
• WordPress Code Reference: utf8_uri_encode()
• WordPress Code Reference: wp_unique_post_slug()
• WordPress Code Reference: wp_old_slug_redirect()
• Google Search Central: URL structure best practices for Google Search