Ads.txt (Authorized Digital Sellers) is an IAB initiative that lets publishers declare which ad networks are authorized to sell their ad inventory. It prevents ad fraud by making it clear which sellers are legitimate.

Where should ads.txt be placed?

Ads.txt must be placed at the root of your domain (e.g., example.com/ads.txt). It cannot be in a subdirectory.

Do I need ads.txt for Google AdSense?

Yes. Google strongly recommends publishers using AdSense have an ads.txt file. Without it, some buyers may reduce or stop buying your inventory, leading to lost revenue.

Free Tool

Ads.txt Checker

Check if a website has a valid ads.txt file declaring authorized digital sellers. Protect your ad inventory and prevent fraud.

What is Ads.txt?

Ads.txt (Authorized Digital Sellers) is an IAB Tech Lab initiative that allows publishers to publicly declare which companies are authorized to sell their digital ad inventory. By placing an ads.txt file at your domain root, you help buyers verify that they are purchasing legitimate inventory — dramatically reducing ad fraud and improving the value of your ad space.

Why Does Ads.txt Matter?

Prevent Ad Fraud

Ads.txt stops unauthorized sellers from misrepresenting your inventory to ad buyers, protecting your revenue and reputation.

Required for AdSense

Google recommends publishers have ads.txt for AdSense. Missing entries can cause Google to reduce or pause ad buying on your site.

Declare All Partners

List every ad network, SSP, and reseller authorized to sell your inventory. Buyers check this file before purchasing.

Boost CPMs

Verified inventory commands higher CPMs. Advertisers pay more for inventory backed by a valid ads.txt.

Ads.txt Format Example

# Ads.txt for example.com
# Contact: ads@example.com
CONTACT=ads@example.com

# Google AdSense / Ad Manager
google.com, pub-0000000000000000, DIRECT, f08c47fec0942fa0

# Another network
adnetwork.com, 12345, DIRECT
anothernetwork.com, 67890, RESELLER