Content Quality
Content Quality analyses how readable, well-structured, and up-to-date the page's text is — factors that affect both user experience and Google's Helpful Content assessment. Weight: 10%.
Details
Flesch Reading Ease
Flesch Reading Ease is a formula that scores text readability from 0 (very hard) to 100 (very easy). CheckSEO uses language-adaptive formulas:
• English: standard Flesch formula based on average sentence length and syllables per word
• Russian: Flesch-Oborneva adaptation with different coefficients tuned for Cyrillic text
The language is auto-detected by the ratio of Cyrillic characters in the text.
Score interpretation: ≥80 = easy, 60–79 = moderate, 40–59 = medium difficulty, 20–39 = difficult, <20 = very difficult.
A Flesch score below 40 triggers a warning.
Sentence length
Long sentences are harder to read and scan. Google's NLP models also parse shorter sentences more reliably. Aim for an average sentence length of 15–20 words.
The audit flags two related issues:
• Average sentence length > 25 words → warning
• More than 5 individual long sentences (>25 words each) → warning
The total sentence count and count of short paragraphs (<20 words) are also reported.
Content freshness
Google rewards regularly updated content for time-sensitive queries. The audit checks multiple sources for date signals (in priority order):
• Meta tags: article:published_time, article:modified_time, datePublished, dateModified, dc.date, last-modified
• JSON-LD fields: datePublished, dateModified, dateCreated
• HTML <time> tags with datetime attribute
• HTTP Last-Modified response header
• Copyright year pattern (© YYYY) in body text
Content older than 12–18 months without updates may lose ranking for freshness-sensitive queries.
Keyword density
Keyword density measures how frequently specific words appear relative to the total word count. Over-optimised pages that repeat a keyword unnaturally (keyword stuffing) can trigger a spam penalty.
The audit extracts the top 20 words by frequency (excluding stop words, minimum 3 characters) and flags any word exceeding a 3.0% density threshold. This is a hard threshold, not a range — anything above 3% is considered over-optimised.
A natural distribution across synonyms and related terms is preferred over repeating a single keyword.
Metrics
| Metric | Description |
|---|---|
| Flesch Reading Ease | Readability score 0–100. Higher = easier to read. Uses language-adaptive formula (English or Russian). |
| Readability level | Descriptive level: Easy / Moderate / Medium / Difficult / Very Difficult. |
| Avg sentence length | Mean number of words per sentence. >25 triggers a warning. |
| Word count | Total word count analysed for readability and density. |
| Top keywords | Most frequent words and their density percentage (top 20, stop words excluded). |
| Over-optimised words | Words exceeding the 3% keyword density threshold. |
| Date metadata | Whether any date signal (datePublished, dateModified, etc.) is present. |
| Published date | Whether a datePublished is found in structured data or meta tags. |
| Modified date | Whether a dateModified is found in structured data, meta tags, or Last-Modified header. |
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