🎯 Primary Keyword
One main keyword or phrase📄 Your Content
Paste at least 300 words for meaningful analysis📚 Competitor Content (optional)
Paste 1–5 competitors separated by a line with---
📝 Content Brief
Run the analyzer first. The brief is auto-generated from your keyword and competitor set.
⚖️ You vs. Competitors
Side-by-side metrics comparison. Higher is better unless marked otherwise.
📜 Analysis History
Your last 30 analyses, saved only in your browser.
How the SEO Content Analyzer Works
This tool runs entirely in your browser using deterministic NLP algorithms. No external API calls, no AI models, no data leaves your device.
Content Score (0–100)
The overall score is a weighted combination of six sub-scores:
| Sub-score | Weight | What it measures |
|---|---|---|
| Keyword Density | 20% | Primary + secondary keyword coverage vs. ideal 1–2% range |
| Semantic Coverage | 25% | How many top TF-IDF terms from the topic cluster you include |
| Structure | 15% | H2/H3 headings, lists, paragraph length |
| Length | 15% | Word count vs. competitor average |
| Readability | 15% | Flesch Reading Ease (target 55–70) |
| Entity Coverage | 10% | Named entities present in your content vs. competitors |
TF-IDF Explained
TF-IDF stands for Term Frequency – Inverse Document Frequency. It's the classic information-retrieval algorithm that surfaces terms uniquely important to a topic cluster:
- TF = how often a term appears in the current document ÷ total words in that document
- IDF = log(total documents ÷ documents containing the term)
- Score = TF × IDF
Terms with the highest TF-IDF scores are the semantic pillars of the topic. If your content is missing them, search engines may interpret your article as off-topic.
Entity Extraction
The tool uses rule-based NLP to detect:
- Capitalized word sequences that aren't sentence-starters
- Named patterns like "Google Analytics" or "Pimpri-Chinchwad"
- Domain-specific terms present in competitor sets
If a named entity appears in 2+ competitor articles but not in yours, it's flagged as a "gap entity" — a strong signal you're missing content the SERP rewards.
Readability (Flesch Reading Ease)
Calculated as: 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). Scores above 60 are considered easy for a general audience.
PAA Question Generation
Questions are generated by combining the primary keyword with 15+ interrogative templates ("how to", "what is", "why", "when", "best", "vs", "guide", "for beginners", "near me", etc.) that mirror real People Also Ask query patterns. All suggestions are syntactic — we never claim they are actual Google PAA results.
Limitations — honest disclosure
- The tool does NOT connect to Google Search Console, SERP APIs, or Google Trends.
- Competitor analysis is based on what you paste in — it does not scrape SERPs.
- Entity extraction is heuristic (no spaCy, no BERT). It works well on business/technical content and less well on poetry or experimental writing.
- TF-IDF is best with 3–5 competitor documents. With only one, it degrades to simple term-frequency.
- Scores are directional. Always combine with human judgement and actual GSC data.
Frequently Asked Questions
Is this SEO content analyzer free?
Yes — completely free, no signup, no ads, no usage limits. All analysis runs in your browser.
Does it work without competitor content?
Yes. The tool will still analyze keyword density, structure, readability, and generate PAA questions. But TF-IDF and gap-entity detection become far more powerful when you paste 3–5 competitors that currently rank for your keyword.
How is this different from Surfer SEO or Frase?
Those tools charge $99–$299/month and connect to live SERP data. This tool is free, has no API keys, and runs client-side. The algorithms (TF-IDF, entity extraction, readability formulas, keyword density) are the same mathematical foundations. You trade automatic SERP scraping for zero cost and complete privacy.
What is a good content score?
85+ is excellent. 70–85 is competitive. 55–70 has visible gaps worth fixing. Below 55 usually means the content is either too short, off-topic, or missing key semantic terms.
What is a "gap entity"?
A named entity (person, place, organization, concept) that appears in 2+ competitor articles but not in yours. Example: if competitors mention "Google Analytics 4" and "Search Console" but your article doesn't, those are gap entities — and likely reasons you may not rank.
How many competitors should I paste?
3 to 5 is ideal. Fewer than 2 makes IDF meaningless. More than 8 slows the analysis and dilutes the top-term signal.
Can I use this for non-English content?
The stopword list and readability formulas are tuned for English. Keyword density, TF-IDF, and structure analysis work on any Latin-script language. Non-Latin scripts (Devanagari, Arabic, etc.) will pass through but with reduced accuracy.
Is my content stored on a server?
No. All analysis runs in JavaScript in your browser. History is stored in your browser's local storage and can be cleared at any time.
What is the minimum content length?
We recommend 300+ words. Below 200 words, keyword density, TF-IDF, and readability metrics become unreliable.
Does a high score guarantee rankings?
No. No tool can guarantee rankings. A high score means your content is comprehensive and aligned with the topic cluster — but ranking also depends on authority, backlinks, technical SEO, user signals, and SERP layout.