Markdown SEO Analyzer
Analyze markdown content for SEO best practices: heading structure, links, image alt text, readability, keyword density, and frontmatter metadata
Enter your markdown content to analyze for SEO best practices
What is the Markdown SEO Analyzer?
The Markdown SEO Analyzer is a client-side tool that inspects your markdown content for SEO best practices and content quality. It evaluates heading structure, link usage, image accessibility, readability metrics, keyword distribution, and frontmatter metadata — then provides a quality score with prioritized recommendations for improvement.
How to Use
- Paste your markdown content (including frontmatter if present) into the input field
- Click "Analyze" or wait for automatic processing
- Review findings organized by severity (Critical, High, Medium, Low)
- Check the readability metrics and keyword density report
- Export a full report in JSON or Markdown format
Example: Markdown with SEO Issues
This markdown has several issues the analyzer will detect:
### Getting Started
This is a short paragraph.
[click here](https://example.com)
[](#)What Issues Are Detected?
- Missing H1 — Every page needs exactly one H1 heading for topic identification
- Heading hierarchy skips — Jumping from H1 to H3 breaks the logical document outline
- Images without alt text — Missing alt attributes hurt accessibility and image search rankings
- Empty anchor text — Links without descriptive text provide no context to users or search engines
- Thin content — Content under 300 words may not rank well for competitive topics
- Long sentences/paragraphs — Overly dense text reduces readability and engagement
- Keyword stuffing — Repeating words above 5% density may trigger search engine penalties
- Missing frontmatter — Without title and description metadata, CMS and SSGs cannot generate proper meta tags
Readability Metrics Explained
The analyzer calculates word count, sentence count, paragraph count, average words per sentence, average words per paragraph, and estimated reading time. These metrics help you write content that is both comprehensive enough for SEO and readable enough for engagement.
- Word count — Aim for 300+ words for informational content, 1000+ for pillar pages
- Sentence length — Target 15-20 words per sentence for optimal readability
- Paragraph length — Keep paragraphs to 3-5 sentences for easy scanning
- Reading time — Calculated at 200 words per minute average reading speed
Frontmatter Best Practices
YAML frontmatter at the top of your markdown files provides metadata to static site generators. Include these fields for optimal SEO:
---
title: "Your Page Title (50-60 chars)"
description: "Compelling meta description (120-160 chars)"
keywords: [primary keyword, secondary keyword]
---Privacy and Security
All analysis happens entirely in your browser using JavaScript. Your markdown content — which may include draft articles, proprietary documentation, or unpublished content — is never transmitted to any server. No data is stored, logged, or shared.
Frequently Asked Questions
What does the Markdown SEO Analyzer check?
The analyzer checks heading structure (H1 presence and hierarchy), internal and external links, image alt text, readability metrics (word count, sentence length, paragraph length), keyword density, and YAML frontmatter metadata. Each issue is scored by severity and contributes to an overall SEO quality score.
Why is heading hierarchy important in markdown?
Search engines use headings to understand page structure and topic hierarchy. A single H1 identifies the main topic, H2s mark major sections, and H3s mark subsections. Skipping levels (e.g., H1 to H3) confuses crawlers and assistive technologies, potentially hurting both SEO rankings and accessibility.
What is considered 'thin content' for SEO?
Content under 300 words is generally considered thin for informational pages. While word count alone doesn't determine quality, search engines tend to favor comprehensive content for competitive queries. For most blog posts and documentation pages, aim for 500-2000 words covering the topic thoroughly.
How does keyword density affect SEO?
Keyword density is the percentage of times a word appears relative to total word count. Natural content typically has 1-3% density for primary keywords. Density above 5% may signal keyword stuffing to search engines, potentially triggering ranking penalties. Use natural variations and synonyms instead of repeating the same word.
Why should images have alt text in markdown?
Alt text () serves two purposes: it provides accessible descriptions for screen reader users, and it helps search engines understand image content for image search rankings. Missing alt text hurts both accessibility scores and SEO. Use descriptive text that explains what the image shows.
What is YAML frontmatter and why does it matter for SEO?
YAML frontmatter is a metadata block at the top of markdown files (between --- delimiters) used by static site generators like Astro, Hugo, Jekyll, and Next.js. Fields like title, description, and keywords map to HTML meta tags that search engines use for indexing and displaying search results.
What makes a good meta description in frontmatter?
A good meta description is 120-160 characters, includes relevant keywords naturally, describes the page content accurately, and encourages clicks from search results. It should be unique per page and not duplicated across your site. Think of it as a mini-advertisement for your content.
Is my markdown content sent to any server for analysis?
No. All analysis runs entirely in your browser using JavaScript. Your markdown content — which may contain draft articles, proprietary documentation, or unpublished content — never leaves your device. No data is stored, logged, or transmitted to any server.