URL Has Double Slash

Element Code: UR-007

What a double slash URL actually is

This check flags URLs that contain two consecutive slashes inside the path: https://example.com/blog//my-post/ or https://example.com//category/page. To be clear about what does NOT count: the two slashes after https: are the scheme separator and are supposed to be there. The problem is repetition after the hostname.

Here is the part people underestimate: by the URL standard (RFC 3986), /blog//my-post/ and /blog/my-post/ are two different URLs. An empty path segment is still a segment. Some servers and frameworks normalize the double slash away, but plenty of stacks, including default Apache and nginx setups fronting a CMS, will serve identical content on both with a 200 status. At that moment you have two live addresses for one page, and search engines treat them exactly that way.

Where double slashes come from

In nearly every audit where I have chased these down, the culprit was string concatenation. A base URL stored with a trailing slash gets glued to a path that starts with a slash: site.com/blog/ + /my-post = site.com/blog//my-post. Classic sources:

A misconfigured site URL or environment variable with a trailing slash. Template code building hrefs by hand instead of using the framework's URL helper. Migration or redirect regex rules that append a slash to something that already had one. Breadcrumb or pagination components with a hardcoded leading slash. CDN or reverse proxy rewrites layered on top of origin rewrites. And occasionally external sites linking to you with a mangled URL, which you cannot prevent, only absorb with a redirect.

Why it matters for SEO

One double slash URL is trivial. The mechanism behind it never produces one. A template bug repeats on every page that uses the template, so you wake up to a crawl where 4,000 URLs exist twice. The consequences stack up predictably: Google spends crawl budget fetching duplicates instead of new content, internal links and any external links pointing at the malformed variant split ranking signals across two addresses, and Search Console fills with "Duplicate without user-selected canonical" noise that buries real problems. Relative links on a double slash page can also resolve against the wrong base path and spawn even deeper malformed URLs, which is how a small bug turns into a crawl trap. Nobody gets penalized for this, but it is friction you are choosing to keep.

How to detect it

Crawl the site with Screaming Frog and use Search, or a custom filter, for URLs matching a path double slash. The regex https?://[^/]+.*// catches them while ignoring the scheme separator. Sitebulb flags these natively under URL issues. Then check your server logs or Cloudflare analytics for requests containing // in the path to see whether bots are actually hitting the variants, and pull the Pages report in Search Console filtered to duplicate statuses to see if any got indexed. Finally, click through a flagged URL and note the response: a 200 confirms the duplication is live, a 301 to the clean URL means the server is already defending itself and you only need to fix the internal links.

How to fix it, step by step

1. Find the generator first. Open a flagged URL's linking pages in Screaming Frog (Inlinks tab) and identify the template producing the bad href. Fixing the redirect without fixing the source leaves you with thousands of internal 301 hops forever.

2. Fix the concatenation. Normalize your base URL to no trailing slash, or run every constructed URL through the framework's path join or URL helper. One line of defensive code kills the whole class of bug.

3. Add a server-side collapse rule so external links and stragglers land correctly. Nginx: merge_slashes on; handles it at parse time (it is actually the default; someone usually switched it off). Apache: a mod_rewrite rule like RewriteCond %{THE_REQUEST} // followed by a 301 to the cleaned path. Test with curl before and after.

4. Confirm canonicals. Every page should self-reference the clean URL, so even a surviving duplicate points its signals home.

5. Recrawl and verify zero remaining internal links to double slash URLs, and spot-check that the 301s resolve in a single hop.

What good looks like

A clean site returns exactly one 200 URL per page. Requesting any double slash variant answers with a single 301 to the canonical path, no internal link anywhere emits a //, and your crawler's URL report for this check reads zero. Ten minutes of curl testing after each release keeps it that way.

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