Website Categorization API | Domain Category Check | WhoisXML API

#1 Website Categorization API to define web domain categories

Website Categorization API uses a machine learning (ML) engine to scan a website’s content and meta tags. It extracts text to classify the site and assign the top Internet Advertising Bureau (IAB) categories applicable to it with associated confidence scores aided by natural language processing (NLP).

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100 free API requests monthly. No credit card required.

Check the complete list of 500+ categories here.
230 Million+Websites parsed
4 Million+Websites parsed daily
52,000+Satisfied customers

Benefits of our website classification API

  • Relevance

    By using a combination of advanced ML algorithms and human assistance, we categorize 4+ million web pages daily.

  • Compatibility

    Use Website Categorization API with the Domain Research Suite (DRS) to obtain additional ownership details from WHOIS records such as contact and registrant details for any website of interest.

  • Precise

    We support the 500+ categories identified by the IAB. Results also reflect each category’s IAB identification number and corresponding confidence scores.

Practical usage

Brand abuse prevention and marketing

Brand abuse prevention and marketing

Steer clear of websites pertaining to undesirable categories. Align media placements with your desired brand messaging.

Contextual targeting

Scour web pages to gain contextual insights on featured brands, topics, or keywords. Website Categorization API is a useful source of information for targeting the right audiences and monetizing campaigns.


Find opportunities for profit. Obtain and qualify leads based on the specified categories of your best customers.

Malware detection and content filtering

Investigate threats at the domain level and identify malicious activities such as malware, phishing, fraud, and spyware.

You can easily block bad content within your application, appliance, or company network. Just query our API with the requested domain name and reject it if the categories it belongs to are not part of your “approved” list.

Malware detection and content filtering
Data integration

Data integration

Build your own products and enrich them with our high-value data. Every API output comes in JavaScript Object Notation (JSON) format, which can be read and integrated into your product easily.

Website Categorization API

Website Contacts & Categories Database

We provide a daily updated, well-structured database of domain names classified into 25 different categories with their owner contact information. Every day, we parse more than 4 million websites.

Order database
Website Categorization API

Get 100 free API requests monthly. No credit card required.

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Premium API Services

Our APIs are available in an enhanced version that offers better performance with a dedicated load balancer and a premium endpoint to enable faster throttling for large-scale API deployments.

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Enterprise API Packages

Tired of constantly renewing subscriptions? Get a year’s worth of API access. The amount you pay depends on the desired query volume that matches your business requirements.

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