HTML / XML / JS, low-level validity (cross-cutting)MediumInferred
Encoding mismatch
If the declared charset and the actual encoding disagree, characters render as mojibake. The charset declaration must match how the file is actually encoded, normally UTF-8.
What it is
Declared charset ≠ actual.
Why it matters
Garbled text; parsing issues.
How to fix it
Serve and declare UTF-8 consistently.
How to find it on your site
- Check the declared charset against the actual file encoding.
- Look for garbled characters on the page.
- Serve and declare UTF-8 consistently, in the meta and the HTTP header.
- Re-check special characters render correctly.
Cross-reference to ranking and citation factors
An encoding mismatch corrupts text rendering. Consistent UTF-8 keeps characters correct everywhere.
Impact
Low-medium. Inferred.
Evidence
Correct encoding supports parsing. Google Search Central, In-Depth Guide to How Google Search Works