What app-ads.txt is
app-ads.txt (Authorized Sellers for Apps) is a plain text file defined by the IAB Tech Lab. It lists every ad network and reseller allowed to sell ads in your app. Before an ad network buys or fills your inventory, it reads the file on your developer website and checks that its own seller ID is listed. If the file is missing or does not list the network, many buyers skip your app and your fill rate and eCPM drop.
It is the mobile counterpart of ads.txt for websites: same format, but it lives on the developer website declared in your App Store or Google Play listing.
Where the file must live
Ad networks do not look for app-ads.txt inside your app. They take the developer website from your store listing and request /app-ads.txt at the root of that domain, for example https://your-app.freeprivacypolicy.app/app-ads.txt. Three rules decide whether verification passes:
- The file sits at the root of the exact domain listed as developer website in App Store Connect or the Google Play Console.
- It answers with HTTP 200 and
text/plain, without a login wall or an HTML error page. - Every network you use has its line, with the right publisher ID.
Most indie developers do not have a website, and that is where app-ads.txt setups usually fail.
The line format
Each line has three required fields and one optional field, separated by commas:
google.com, pub-1234567890123456, DIRECT, f08c47fec0942fa0
applovin.com, 0123456789abcdef, DIRECT
unity.com, 1234567, DIRECT, 96cabb5fbdde37a7- The ad system domain (
google.comfor AdMob). - Your publisher or account ID in that system.
DIRECTwhen you own the account,RESELLERwhen a partner sells on your behalf.- Optional certification authority ID (the TAG ID).
Copy each line from the dashboard of the network (AdMob shows it under Apps, app-ads.txt). Mediation platforms such as AppLovin MAX and ironSource publish a full list of partner lines to paste.
How we host it for you, free
Every policy you publish here gets its own address, such as your-app.freeprivacypolicy.app, with your privacy policy, terms, EULA and child safety page. The same address serves /app-ads.txt and /ads.txt:
- You paste your lines in your company profile. We trim them, remove duplicates and serve them as
text/plain. - The app-ads.txt of an address merges the lines of every company you own, so one developer website covers all your apps.
- Changes are live immediately. There is nothing to deploy and no DNS to change.
- Your AI assistant can update the lines for you over MCP, and the REST API accepts them too.
Then use that address as the developer website (Google Play: Store settings, Website; App Store Connect: Marketing URL or Support URL of your app) and link its /privacy-policy in the privacy policy field of both stores.
Set it up in four steps
- Create your policy with the guided questions and publish it. You get your address.
- Open your company, paste the lines from AdMob and your other networks into app-ads.txt, and save.
- Put the address in the developer website field of your App Store and Google Play listings.
- In AdMob, open Apps, app-ads.txt and click Check for updates. Verification usually completes within 24 hours after the stores pick up the new website.