WebsiteCategorizationAPI
Home
Demo Tools - Categorization
Website Categorization Text Classification URL Database Taxonomy Mapper Carbon Footprint
Demo Tools - Website Intel
Technology Detector Quality Score Competitor Finder
Demo Tools - Brand Safety
Brand Safety Checker Brand Suitability Quality Checker
Demo Tools - Content
Sentiment Analyzer Context Aware Ads
Resources
API Documentation Pricing Login
Try Categorization
Proven & Deployed

IAB Content Taxonomy v2

698 categories across four tiers, still powering billions of programmatic impressions every day. Our API returns v2 and v3 classifications simultaneously — backward compatibility built into every call.

698Categories
4Tier Levels
6Taxonomies Supported
102MDomains Pre-classified
Legacy DSP Support
Header Bidding
Private Marketplace Deals
Cross-Platform Targeting
Contextual Advertising
Publisher Monetization
Backward Compatibility

Why IAB v2 Still Matters

The IAB Content Taxonomy v3 is the latest standard, but the reality of programmatic advertising tells a different story. Billions of dollars in ad spend still flow through v2 pipelines every quarter. Major demand-side platforms, supply-side platforms, and data management platforms built their entire targeting and reporting infrastructure on v2 category IDs — and many have not fully migrated.

Dropping v2 support means losing compatibility with a significant share of the open exchange. Our API eliminates that risk entirely: every single classification call returns both v2 and v3 categories simultaneously, at no extra cost. You stay compatible with legacy partners while giving v3-ready platforms exactly what they need.

  • Dual-taxonomy response in every API call
  • No configuration flags — v2 is always included
  • Confidence scores on every category tier
  • 102 million domains pre-classified in both taxonomies
v2 → v3 Mapping Example
Arts & Entertainment
Fine Art
Movies
Television
Technology & Computing
Computing
Consumer Electronics
Artificial Intelligence
Four-Tier Depth

Granular Category Structure

Every URL is classified from broad vertical down to the most specific sub-category. Four tiers of depth mean you can target at the level that matches your campaign — from top-level verticals for reach, to leaf categories for precision.

Tech Path

1Technology & Computing
2Consumer Electronics
3Smartphones
4Android Phones

Sports Path

1Sports
2Team Sports
3Football
4NFL

Finance Path

1Personal Finance
2Investing
3Stocks
4Growth Stocks
698Categories in the IAB v2 taxonomy
23Top-level verticals covering every content type
v2 + v3Dual taxonomy returned in every single API call
102MDomains pre-classified in the offline database
23 Verticals

Top-Level IAB v2 Categories

Each of these 23 verticals branches into three deeper tiers, giving you 698 precise classification targets for contextual advertising, brand safety, and audience segmentation.

Arts & Entertainment
Automotive
Business
Careers
Education
Family & Parenting
Food & Drink
Health & Fitness
Hobbies & Interests
Home & Garden
Law, Gov & Politics
News
Personal Finance
Pets
Real Estate
Religion & Spirituality
Science
Shopping
Society
Sports
Style & Fashion
Technology & Computing
Travel
Zero-Configuration

Dual Taxonomy in Every Call

You never have to choose between v2 and v3. Every classification request returns both taxonomies simultaneously, with independent confidence scores for each. There is no configuration flag, no add-on cost, no second API call. One request, two complete taxonomies.

This means your v3-ready systems get the latest category granularity while your legacy integrations continue to receive the v2 IDs they depend on — from the same endpoint, in the same response, in the same millisecond.

  • Single endpoint, dual taxonomy output
  • Independent confidence scores per taxonomy
  • No migration downtime or flag toggles
  • Full offline database coverage in both versions
API Response
{
  "iab_v2": [
    {"category": "Sports",
     "confidence": 0.96},
    {"category": "Sports > Football",
     "confidence": 0.88}
  ],
  "iab_v3": [
    {"category": "Sports > Football",
     "confidence": 0.95},
    {"category": "Sports > American Football",
     "confidence": 0.91}
  ]
}
Use Cases

How Teams Use IAB v2 Classification

From DSPs still running v2 seat logic to publishers tagging inventory for private marketplace deals, the v2 taxonomy is woven into workflows that cannot be interrupted.

Legacy System Compatibility

Feed v2 category IDs directly into DSPs, SSPs, and data management platforms that have not yet migrated to v3. No middleware translation layer, no mapping tables — the API output is ready to ingest as-is.

Learn more

Programmatic Bid Enrichment

Attach IAB v2 content signals to bid requests in real time. Classification completes within the OpenRTB auction window, giving your bidder richer contextual data without adding timeout risk.

Learn more

Publisher Inventory Tagging

Auto-tag every article and page in your CMS with v2 categories so ad ops can package contextual segments for direct and programmatic buyers. Consistent classification replaces manual tagging across thousands of pages.

Learn more

Cross-Taxonomy Mapping

Use the dual v2/v3 response as a live Rosetta Stone. Every call gives you both taxonomies for the same URL, so you can build and validate your own mapping tables without manual category-by-category alignment.

Learn more

Offline Database Matching

License our 102-million-domain offline database with v2 categories pre-computed. Match your URL inventory in bulk without any API calls — ideal for data warehouses, analytics pipelines, and offline audience modeling.

Learn more

Custom Category Blending

Combine v2 categories with our web filtering, IPTC, or Google Shopping taxonomies in a single response. Layer multiple classification systems to build unique targeting segments that no single taxonomy can express alone.

Learn more
Integration

Classify in Three Lines of Code

A single POST request returns the full dual-taxonomy classification. No SDK required — any language with an HTTP client works out of the box.

import http.client

conn = http.client.HTTPSConnection(
    "www.websitecategorizationapi.com")

payload = 'query=espn.com' \
          '&api_key=your_api_key' \
          '&data_type=url'

headers = {
  'Content-Type':
    'application/x-www-form-urlencoded'
}

conn.request("POST",
  "/api/iab/iab_web_content_filtering.php",
  payload, headers)

res = conn.getresponse()
data = res.read()
print(data.decode("utf-8"))

Full IAB v2 Classification in Every API Call

698 categories, dual-taxonomy output. Backward-compatible with every platform, forward-ready with v3 in the same response.

Stay in the loop

You are on the list!

We will send you updates that matter — no spam.