Checks
URL character conventions
Checks that a URL's path uses lowercase letters and hyphens only, flagging underscores or uppercase letters that break the convention search engines expect.
What this check looks for
This check inspects the URL's path component for underscores and uppercase letters. Either found warns, naming which problem was detected. A path using only lowercase letters and hyphens (or no letters/underscores at all) passes.
Why it matters
Google has long recommended hyphens over underscores in URL paths because it treats a hyphen as a word separator (noise-cancelling reads as two words) while an underscore is treated as a joining character (noise_cancelling can read as one token), which subtly affects how the URL's words are parsed for relevance. Mixed-case URLs create a different problem: most web servers treat paths as case-sensitive, so /Headphones and /headphones can resolve as two entirely different (or one broken) URL depending on server configuration, creating accidental duplicate-content or 404 risk. Clean, consistent, lowercase-hyphenated URLs are also simply easier to read, type, and trust — a small detail that compounds with the site's overall professionalism.
How to fix it
Use lowercase, hyphen-separated path segments and 301-redirect any old URLs using the wrong convention:
# Uses underscores and mixed case
https://www.acme.com/Audio/Wireless_Headphones
# Fixed
https://www.acme.com/audio/wireless-headphonesSet this convention once in your URL-generation logic (slug creation from titles) rather than relying on manual consistency across every new page.
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