What we check on the site

The list of rules is regularly updated and expanded, outdated rules are removed.

Canonical tag

The `canonical` tag was not found.

The `canonical` tag must be present on every page of the site and link to the main mirror of the page.

Format of the `canonical` meta tag

The `canonical` tag must contain a complete valid URL.

Duplicate the `canonical` tag.

Only one `canonical` tag should be present on the page.

Images

The presence of the `src` attribute of the <img> tag

Every image must contain a `src` attribute with a valid image url.

The validity of the `src` attribute of the <img> tag

Every image must contain a `src` attribute with a valid image url.

The presence of the `alt` attribute of the <img> tag

Each image must contain an `alt` attribute describing the content of the image.

Using the `alt` and` title` attributes together.

Image must not have `alt` and` title` attributes at the same time.

META Description tag

The presence of the meta-tag `description`

The meta tag `description` should be on every page.

The length of the `description` meta tag

The optimal length for the value of the META tag `description` is between 50 and 160 characters.

Duplicate the `description` meta tag.

Only one `description` meta tag must be present on the page.

OpenGraph tags

Presence of og: image

Every page is recommended to have an OpenGraph `og: image` tag.

Correctness og: image

OpenGraph the `og: image` tag must contain a full valid url.

Presence of og: sitename

Every page is recommended to have an OpenGraph tag `og: sitename`.

Presence of og: title

Every page is recommended to have an OpenGraph `og: title` tag.

Presence of og: type

Every page is recommended to have an OpenGraph `og: type` tag.

Presence of og: url

Every page is recommended to have an OpenGraph `og: url` tag.

Correctness og: url

OpenGraph the `og: url` tag must contain a full valid url.

Having twitter.card

Every page is recommended to have an OpenGraph tag `twitter: card`.

Correct twitter.card

The OpenGraph `twitter.card` tag must contain one of the following: summary, summary_large_image, app, player.

Availability of twitter.description

Every page is recommended to have an OpenGraph tag `twitter: description`.

The presence of twitter.domain

Every page is recommended to have an OpenGraph tag `twitter: domain`.

Correct twitter.domain

OpenGraph the `twitter.domain` tag must contain a fully valid url.

Having twitter: image

Every page is recommended to have an OpenGraph tag `twitter: image`.

Correct twitter: image

OpenGraph the `twitter.card` tag must contain a fully valid url.

Availability of twitter: site

Every page is recommended to have an OpenGraph tag `twitter: site`.

Tag <h1>

The presence of the <h1> tag

Each page must contain a heading in the form of an <h1> tag

Presence of several <h1> tags

Only one <h1> tag should be on the page.

The length of the <h1> tag

The optimal length for the <h1> tag is 10 to 80 characters.

Page title

Availability of <title>.

Each page must contain a title in the form of a <title> tag

The length of the <title> tag

The optimal length for the <title> tag is 10 to 80 characters.

Duplicate the `title` tag.

Only one `title` tag must be present on the page.

Status codes of responses

Find broken links

The site must not contain broken links.

Checking the status of the response code

The expected response status codes are 2xx.