AdSense for Search (AFS) and Custom Search Ads

AdSense for Search, AFS, is Google's umbrella for letting partners earn from search ads on their own pages. It is the root of the Google feed. Every other Google search product for publishers, including RSOC, sits on top of an AFS contract.

Two things with one name

The name causes confusion because it covers two products.

When practitioners say "an AFS feed", they mean Custom Search Ads: Google's script requests ads for a query and draws them into a container on the partner's page.

How the CSA code works

The integration is client-side. Google's JavaScript runs in the visitor's browser, so Google sees the real device, browser and page. This is a deliberate design: it lets Google measure and police the traffic directly. The page passes a set of page-level options and one or more ad blocks.

The heart of AFS policy: where did the query come from?

Advertisers buying search ads are paying for a person's own stated need. So the AFS program policies centre on one question: did a real user choose this query? Google's policy page accepts three sources only.

1. Typed by the userEntered and submitted in a search box monetisation, with no editing, modification or filtering by the publisher. Search boxes may not be pre-filled, and links that carry pre-filled terms are not allowed.
2. A compliant product-integrated featureSearch access built into a product, under a separate and detailed Google policy. This is the narrow route that applies to things like browser extension search monetisation.
3. An alternative search queryA suggested term the user clicks, such as related searches. Google's policy says such terms must aim to suggest the most relevant queries and must not be designed to trigger particular ads or inflate clicks.

Anything else is out. A page that silently inserts a commercial keyword the user never chose is using forced keywords, which is a form of keyword stuffing and a quick way to lose a feed.

Other rules practitioners trip over

• No incentives. Users may not be paid or rewarded for searching or viewing ads. See incentivised click.
• No tampering. The code may not be modified, and results may not be framed.
• Not inside software. The standard policy bars placing the code in toolbars or extensions; those need the product-integrated route.
• Related search on results pages is limited to two units per page, with rules on position and labelling, and fewer than three terms will not display.
• Site approval. Google introduced site-level approval for AFS in March 2024, according to trade press reports, so each domain must be approved before it can serve.

1. One ad pool, three doors: A search feed lends a search engine’s advertisers to another website. Google has offered it in three main shapes. They differ in one thing: how the visitor’s interest (the search intent) is established before ads appear.
2. Door 1: the visitor types a query: With AdSense for Search, a site has its own search box. The visitor types what they want and the results page carries search ads, drawn by Custom Search Ads code. Like a shop assistant answering the question you asked.
3. One step from query to ad: Because the visitor wrote the query themselves, intent is clear and one ad click pays. Rules are strict about where the query came from: a query the visitor never typed or chose is not a real search.
4. Door 2: the visitor reads first: With Related Search on Content, the visitor lands on an article. A labelled block suggests searches related to what the page is about. The page must have real content; the block is an add-on, not the whole page.
5. Two clicks: topic, then ad: Tapping a suggested term opens a results page with ads for it; clicking an ad is what pays. This two-click flow is the format most paid-traffic arbitrage uses today, because the visitor’s own tap confirms the interest.
6. Door 3: a domain with nothing on it: A parked domain is a web address with no real site. With AdSense for Domains, someone who mistyped an address or followed an old link saw a page of keyword links and ads guessed from the domain name alone.
7. The door Google closed: Intent here was weakest: the visitor never asked for anything. Google Ads opted advertisers out of parked domains by default during 2025 (flipping the usual advertiser opt-out) and removed them from its search partner network on 10 February 2026.
8. The clearer the intent, the safer the feed: Typed query, chosen topic, guessed topic: advertisers pay for intent, and the formats that prove it survive. That is why policy keeps pushing arbitrage toward real content and a genuine choice by the visitor.

Results pages in the two-step funnel

In modern arbitrage the AFS results page is usually the second screen. The visitor chose a term on an article page, and lands here to see ads. The classic alternative is a keyword lander, a page of keyword links with no article, which was the standard design for Yahoo and Bing feeds and for parked domains. Google's direction since 2022 has been clear: content first, ads on the second screen.

What Google watches

Because the code runs in the browser, Google collects its own signals about every request and click. Clicks it judges invalid are not charged to advertisers and are not paid to the partner. Clicks that are valid but convert poorly for advertisers are discounted, a mechanism Google calls smart pricing. Neither is negotiable, and neither is fully visible to the partner. All a publisher sees is RPC drifting down.