Doctype

Checks for valid HTML5 doctype declaration


Rule ID	`core/doctype`
Category	Core SEO
Scope	Per-page
Severity	warning
Weight	5/10

Solution

Add <!DOCTYPE html> at the very start of your HTML document, before the <html> tag. This declaration tells browsers to render the page in standards mode rather than quirks mode, ensuring consistent rendering across browsers. Without a proper doctype, browsers may render the page inconsistently.

Enable / Disable

Disable this rule

squirrel.toml

toml

[rules]
disable = ["core/doctype"]

Disable all Core SEO rules

squirrel.toml

toml

[rules]
disable = ["core/*"]

Enable only this rule

squirrel.toml

toml

[rules]
enable = ["core/doctype"]
disable = ["*"]

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