SEO Auditing API
Extract on-page SEO signals across large site inventories — title tags, meta descriptions, heading structures, canonical URLs, hreflang, and structured data — for programmatic auditing workflows.
How It Works
Crawl the site inventory
Discover all URLs within a domain and generate a page list for systematic auditing.
Extract SEO signals
Pull structured SEO data from each page: title, description, H1-H3, canonical, robots meta, hreflang, and JSON-LD.
Identify issues programmatically
Analyze extracted data to flag missing tags, duplicate titles, broken canonicals, and missing structured data.
Quick Start
curl -X POST https://alterlab.io/api/v1/scrape \
-H "X-API-Key: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"url": "https://example.com/product-page",
"extract": {
"title": "string",
"meta_description": "string",
"h1": "string",
"canonical": "string",
"structured_data": "object"
}
}'Need an API key? — no credit card required.
Related Data Extraction Guides
Related Use Cases
Frequently Asked Questions
What SEO elements can I extract with this API?
Title tags, meta descriptions, canonical URLs, robots meta directives, hreflang attributes, Open Graph tags, Twitter Card tags, H1–H6 headings, JSON-LD structured data, internal links, and image alt attributes.
How do I audit a site with thousands of pages?
Combine AlterLab's crawl discovery with parallel extraction requests. Crawl the sitemap or root domain to generate URLs, then batch-process each URL for SEO signal extraction at scale.
Responsible Use
AlterLab is designed for extracting publicly available data. Always review the terms of service for any website you access, respect robots.txt directives, and ensure your use case complies with applicable laws in your jurisdiction.
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Pricing
From $0.0002/request. No subscriptions. Balance never expires.
Your first scrape.
Sixty seconds.
$1 free credit — up to 5,000 scrapes. No credit card.
Just a POST request.
No credit card required · $1 free credit, up to 5,000 scrapes · Balance never expires