Assessments for SEO and Readability

Pick from 28 different SEO and readability assessments powered by Yoast SEO v3 with improved performance and accuracy.

Overview

Kirby SEO Audit comes with 28 comprehensive assessments that analyze your content for search engine optimization and readability:

17 SEO assessments: Powered by Yoast SEO v3, focusing on keyword optimization, meta data, links, and technical SEO factors
8 Readability assessments: Powered by Yoast SEO v3, analyzing content structure, sentence length, and overall readability
3 Custom SEO assessments: Provided by Kirby SEO Audit to expand on Yoast SEO

All SEO and readability assessments run locally in your browser using the Yoast SEO engine. No external web services or API calls are made, ensuring your data remains private and secure.

The analysis results are organized into three clear categories to help you prioritize optimization efforts, regardless of whether they're SEO or readability assessments:

Category	Description	Priority
Good	✅ Assessments that pass SEO best practices	Green indicators
OK	⚠️ Areas that could be improved but aren't critical	Orange indicators
Bad	❌ Issues that should be addressed for better SEO	Red indicators
Feedback	💡 Suggestions for further improvements	Gray indicators

Kirby SEO Audit v3 upgrades from Yoast SEO v1 to v3, bringing significant improvements in performance, accuracy, and new features. The upgrade introduces web worker support for faster, non-blocking analysis and better content parsing accuracy.

✨ New Assessments

imageKeyphrase – Analyzes if images are optimized for your target keyphrase

❌ Removed Assessments

fleschReadingEase – No longer available in v3
SentenceLengthInDescription – Discontinued assessment
KeywordStopWords – Replaced with improved keyphrase analysis

🔄 Assessment Name Changes

Several assessments have been renamed to match Yoast SEO v3 conventions:

Old Name (v1)	New Name (v3)	Description
`ParagraphTooLong`	`textParagraphTooLong`	Paragraph length analysis
`OutboundLinks`	`externalLinks`	External link assessment
`PageTitleWidth`	`titleWidth`	Page title width check
`TextImages`	`images`	Image usage analysis
`TitleKeyword`	`keyphraseInSEOTitle`	Keyphrase in title
`UrlKeyword`	`slugKeyword`	Keyphrase in URL slug
`KeywordDensity`	`keyphraseDensity`	Keyword density analysis
`SubheadingDistributionTooLong`	`subheadingsTooLong`	Subheading length check
`TransitionWords`	`textTransitionWords`	Transition word usage
`SentenceLengthInText`	`textSentenceLength`	Sentence length analysis

Complete Assessment List

Yoast SEO v3 Assessments

SEO Assessments (17)

The following 17 SEO assessments are powered by Yoast SEO v3:

introductionKeyword – Introduction Keyword
keyphraseLength – Keyphrase Length
keyphraseDensity – Keyword Density
metaDescriptionKeyword – Meta Description Keyword
metaDescriptionLength – Meta Description Length
subheadingsKeyword – Subheadings Keyword
textCompetingLinks – Text Competing Links
imageKeyphrase – Image Keyphrase
images – Text Images
textLength – Text Length
externalLinks – Outbound Links
keyphraseInSEOTitle – Title Keyword
internalLinks – Internal Links
titleWidth – Page Title Width
slugKeyword – URL Keyword
functionWordsInKeyphrase – Function Words in Keyphrase
keyphraseDistribution – Keyphrase Distribution

Readability Assessments (8)

The following 8 readability assessments are powered by Yoast SEO v3:

subheadingsTooLong – Subheading Distribution Too Long
textParagraphTooLong – Paragraph Too Long
textSentenceLength – Sentence Length in Text
textTransitionWords – Transition Words
passiveVoice – Passive Voice
textPresence – Text Presence
sentenceBeginnings – Sentence Beginnings
wordComplexity – Word Complexity

Kirby SEO Audit Custom Assessments

The Kirby SEO Audit plugin provides the following three custom SEO assessments to expand on the Yoast SEO assessments:

singleH1 – Checks whether the content contains exactly one H1 heading.
headingStructureOrder – Checks whether headings (H1 to H6) follow proper sequential order.
altAttribute – Checks whether all images have an alt attribute.

While these custom assessments are not part of Yoast SEO, they are specifically designed with best-practice SEO in mind and complement the existing Yoast SEO assessments.

Custom Assessment Selection

By default, all assessments are enabled. Pick which SEO and readability assessments to include in the report by adding an assessments property to your blueprint, depending on whether you use the view button or section.

buttons:
  seo-audit:
    # Select the assessments you want to include
    assessments:
      - metaDescriptionKeyword
      - metaDescriptionLength
      - titleWidth
      - images
      - textLength
      - imageKeyphrase

type: seo-audit
# Select the assessments you want to include
assessments:
  - metaDescriptionKeyword
  - metaDescriptionLength
  - titleWidth
  - images
  - textLength
  - imageKeyphrase

Assessment names are case-sensitive and must be written exactly as shown above. The new v3 assessment names should be used for proper functionality.

Keyphrase-Dependent Assessments

The following SEO assessments require a keyphrase to be defined via keyphraseField or keyphrase:

functionWordsInKeyphrase
introductionKeyword
keyphraseDensity
keyphraseDistribution
keyphraseInSEOTitle
keyphraseLength
metaDescriptionKeyword
slugKeyword
subheadingsKeyword

If no keyphrase is provided, these assessments will be skipped unless explicitly enabled in the assessments property.

Language-Specific Features

Some assessments are only available in certain languages. The plugin uses the lang attribute of the rendered page's HTML for analysis, while the translations of the SEO results are based on the language selected in the Kirby Panel.

Make sure that the language code in your languages/xx.php file matches the ISO 639-1 language code (e.g., use de for German, not ger).

Assessment	Supported Languages
`wordComplexity`	de, en, es, fr
`keyphraseDistribution`	ar, cs, de, el, en, es, fr, he, hu, id, it, ja, nl, no, pl, pt, ru, sk, sv, tr
`metaDescriptionLength`	ar, cs, de, el, en, es, fa, fr, he, hu, id, it, ja, nl, no, pl, pt, ru, sk, sv, tr
`textParagraphTooLong`	ar, cs, de, el, en, es, fa, fr, he, hu, id, it, ja, nl, no, pl, pt, ru, sk, sv, tr
`textSentenceLength`	ar, cs, de, el, en, es, fa, fr, he, hu, id, it, ja, nl, no, pl, pt, ru, sk, sv, tr
`passiveVoice`	ar, cs, de, el, en, es, fa, fr, he, hu, id, it, nl, no, pl, pt, ru, sk, sv, tr
`textTransitionWords`	ar, ca, cs, de, el, en, es, fa, fr, he, hu, id, it, ja, nl, no, pl, pt, ru, sk, sv, tr
`functionWordsInKeyphrase`	ar, cs, de, el, en, es, fa, fr, he, hu, id, it, nl, no, pl, pt, ru, sk, sv, tr

If a language is not supported by a specific assessment, that assessment will be skipped during the analysis process. Only enable assessments that support your content's language. Alternatively, let the plugin automatically skip unsupported assessments.

View Button & Section

Configure the SEO Audit Panel view button and section in your blueprints with various options.

Audit URL

Customize the target URL used to generate the SEO report and understand how content targeting works.