Glossary
What is Contextual targeting?
Also called: contextual advertising, contextual
Contextual targeting matches ads to the content of the page, such as its topic or category, rather than to what is known about the person reading it.
हिंदी में पढ़ेंWith contextual targeting, a buyer bids because of what the page is about. A brisket guide on a recipe site is about barbecues and grilling, so a grill brand wants it, whoever the reader is. It needs no personal data, so it works whether the reader is logged in, opted out or on Safari.
The shared language is the IAB Tech Lab Content Taxonomy, a numbered list of page topics. In version 3.1, the latest, released in December 2024, category 215 is Barbecues and Grilling, under 210, Food and Drink. A contextual tool maps the page to a category, and your stack sends it in the bid request’s page category field, with a code for the taxonomy version: 9 means 3.1. Version 3 added video, CTV, podcast and gaming topics and dropped old codes, so it is not backwards compatible with 2.x.
Context also protects careful content. Crude keyword blocklists can strip bids from serious journalism, so sending accurate categories helps buyers judge pages on what they really are.
Example
Say a food site has 100,000 page views a day, and 12,000 are on barbecue pages tagged 215. A grill brand's DSP targeting 215 can bid on all 12,000, including readers who opted out or use Safari, because the signal describes the page, not the person.
Why it matters to publishers
Contextual signals work in every browser and need no ID, so they keep pages sellable when identity is missing. Accurate categories also shield careful content from blunt keyword blocks.