Frequently Asked Questions

The Website Categorization API is a service that classifies websites and domains into content categories based on the IAB Content Taxonomy. It analyzes website content and returns standardized category classifications that can be used for content filtering, ad targeting, lead qualification, data enrichment, and many other applications. Our API covers over 500 million domains with 800+ granular categories.

Getting started is easy: Create a free account to get your API key, then follow our API quickstart guide to make your first API call. No credit card is required for the free tier, and you can start categorizing domains within minutes.

Our API is language-agnostic and works with any programming language that can make HTTP requests. We provide code examples for Python, JavaScript/Node.js, PHP, Ruby, Java, C#, and Go. See our API documentation for examples in your preferred language.

Our database contains over 500 million pre-categorized domains. For domains not in our database, we provide real-time classification that analyzes the website content and returns categories instantly. This combination ensures comprehensive coverage regardless of whether a domain has been seen before.

We use the IAB Content Taxonomy, an industry-standard classification system with 800+ categories organized in a hierarchical structure. This taxonomy is widely used in digital advertising, content management, and data classification. View our full category taxonomy for details on all available categories.

Our categorization achieves 95%+ accuracy on standard benchmarks. Each classification includes a confidence score (0-1) indicating how certain the system is about the category assignment. You can use these confidence scores to implement thresholds appropriate for your use case.

Our database is updated continuously. High-traffic domains are recrawled regularly to capture content changes, while real-time classification always returns fresh analysis for any domain. For cached results, we recommend refreshing categorization data every 24-48 hours for most use cases.

Yes! We offer a free tier with 1,000 API calls per month, perfect for testing and small projects. No credit card is required to sign up. When you're ready to scale, you can upgrade to a paid plan with higher limits. See our pricing page for all plan options.

Each domain classification counts as one API call. Batch requests count as one call per domain in the batch. Failed requests (4xx/5xx errors) do not count against your usage. You can monitor your usage in real-time through your dashboard.

When you approach your plan limit, you'll receive email notifications. If you exceed your limit, API calls will return a 429 status code until your quota resets or you upgrade your plan. We offer overage pricing on higher tiers so your applications don't experience interruption.

Pre-cached domains return in under 50ms. Real-time classification for new domains typically completes in 200-500ms depending on website complexity. Our infrastructure is optimized for low latency to support real-time filtering and classification use cases.

Rate limits vary by plan, starting at 10 requests per second on the free tier and scaling to 1000+ requests per second on enterprise plans. See our rate limits documentation for details on each plan and best practices for high-volume usage.

Yes! Our batch endpoint allows you to categorize up to 1,000 domains in a single request, which is more efficient for large-scale processing. See our batch processing guide for implementation details.

Absolutely. All our paid plans include commercial use rights. You can integrate our API into your commercial products, services, and applications. Review our terms of service for specific details on permitted usage.