# Website Categorization API

> websitecategorizationapi.com provides website categorization and domain classification: a real-time URL categorization API, offline URL categorization databases with up to 102M pre-classified domains, and an MCP server for AI agents. Classification uses the official IAB Content Taxonomy 3.0 (703 hierarchical categories with IAB Tech Lab IDs, across 36 Tier-1 groups) and IAB v2 (699 categories) for advertising and brand safety, and a 58-category web content filtering taxonomy for DNS filtering and network security. IPTC NewsCodes, Google Shopping, and Shopify taxonomies are also supported.

Key facts:
- URL categorization databases are delivered as CSV downloads under an annual license with scheduled refreshes, in sizes from 5M to 102M domains (plus a 2.7B-record SNI classification database).
- Published database pricing: Starter 5M domains $2,499 (annual refresh $499/yr); larger tiers (10M-102M, Multi-Category 40M) are quoted on request. AI Agent database: 10M domains $1,599; 20M domains $2,999; 50M domains $4,999.
- Subscriptions: categorized daily registered domains (~300k domains/day) $2,499/month; keywords TF-IDF frequencies on daily registered domains $4,999/month.
- The real-time API classifies websites by URL or domain and returns IAB Content Taxonomy or web-filtering categories with confidence scores.
- Both taxonomies and the filtering-to-IAB mapping are free to download as JSON/CSV from /taxonomy.php.
- Data delivery: CSV download, REST API, or MCP server integration for AI agents and LLM applications.

## Taxonomy and reference data

- [Taxonomy reference](https://www.websitecategorizationapi.com/taxonomy.php): All 703 IAB Content Taxonomy 3.0 categories (with official IAB IDs) and all 58 web filtering categories as HTML tables, with the mapping between them
- [IAB Content Taxonomy 3.0 (JSON)](https://www.websitecategorizationapi.com/data/iab-content-taxonomy-v3.json): 703 categories with official IAB Tech Lab unique IDs, parent IDs, and Tier 1-4 hierarchy
- [IAB Content Taxonomy 3.0 (CSV)](https://www.websitecategorizationapi.com/data/iab-content-taxonomy-v3.csv): Same data in CSV
- [IAB Content Taxonomy v2 (JSON)](https://www.websitecategorizationapi.com/data/iab-content-taxonomy-v2.json): 699 previous-generation IAB category paths, as returned by the v2 endpoint
- [IAB Content Taxonomy v2 (CSV)](https://www.websitecategorizationapi.com/data/iab-content-taxonomy-v2.csv): Same data in CSV
- [Web filtering taxonomy (JSON)](https://www.websitecategorizationapi.com/data/web-filtering-taxonomy.json): 58 categories with descriptions and example domains
- [Web filtering taxonomy (CSV)](https://www.websitecategorizationapi.com/data/web-filtering-taxonomy.csv): Same data in CSV
- [Filtering-to-IAB mapping (JSON)](https://www.websitecategorizationapi.com/data/web-filtering-to-iab-mapping.json): Crosswalk from each filtering category to its closest IAB Content Taxonomy 3.0 path
- [Filtering-to-IAB mapping (CSV)](https://www.websitecategorizationapi.com/data/web-filtering-to-iab-mapping.csv): Same data in CSV

## Products

- [URL categorization database](https://www.websitecategorizationapi.com/url_database.php): Offline databases of up to 102M domains classified into IAB categories; annual license with scheduled refreshes
- [AI agent domain database](https://www.websitecategorizationapi.com/for_ai_agents.php): Domain databases (10M-50M domains) built for AI agents, LLM tools, and autonomous workflows
- [Real-time categorization API](https://www.websitecategorizationapi.com/api.php): REST API returning IAB Content Taxonomy v2/v3 categories for any URL or domain
- [Pricing](https://www.websitecategorizationapi.com/pricing.php): API plans and database price list
- [MCP server](https://www.websitecategorizationapi.com/mcp.php): Model Context Protocol server exposing domain categorization to AI agents (Claude, GPT, and others)
- [MCP real-time API](https://www.websitecategorizationapi.com/mcp-realtime-api.php): Real-time classification via MCP
- [MCP database lookup](https://www.websitecategorizationapi.com/mcp-database-lookup.php): Pre-classified database lookups via MCP

## Documentation

- [Category browser (IAB)](https://www.websitecategorizationapi.com/categories.php): Interactive browser for the IAB category tree
- [Category browser (web filtering)](https://www.websitecategorizationapi.com/filtering_categories.php): Interactive browser for the 58 filtering categories
- [Database integration guide](https://www.websitecategorizationapi.com/integration-guide.php): How to load and query the offline databases
- [Database download API docs](https://www.websitecategorizationapi.com/database-api-docs.php): Programmatic database delivery
- [100 use cases](https://www.websitecategorizationapi.com/100-use-cases.php): Use cases for domain classification data across adtech, security, fintech, and AI agents

## Company

- [Contact](https://www.websitecategorizationapi.com/contact.php): Enterprise sales, custom datasets, and demos; email info@alpha-quantum.com
- [Terms of service](https://www.websitecategorizationapi.com/terms_of_service.php): Licensing terms