An IAB Tech Lab standard that lets app publishers declare which ad networks are authorized to sell their inventory.

Where do I put the app-ads.txt file?

At the root of the developer website listed in your App Store / Google Play page, e.g. https://studio.com/app-ads.txt.

What is a Certification Authority ID?

An optional TAG-ID of the ad system, the 4th field of an app-ads.txt record.

nationalrail.co.uk app-ads.txt check

nationalrail.co.uk is missing out on higher CPMs: its app-ads.txt lists only 41 of the 329 lines its 12 ad networks expect (88% missing). Unlisted sellers can't be verified, so buyers bid less or skip the inventory.

Checked 19 Oct 2026. 165 lines, 95 unique records, 0 duplicates, 0 invalid lines, 12 ad networks detected.

Ad networks in nationalrail.co.uk/app-ads.txt

Google AdMob — accounts pub-1565386861321005, pub-2993845787764317, pub-3004679189235742 and 2 more: 5 lines in the file
Amazon Publisher Services — account bd056b42-51db-43ce-9a8e-3b11319b5d1f: 1 line in the file
Magnite (Rubicon) — accounts 18020, 12556, 18110 and 3 more: 6 lines in the file
Xandr (Microsoft) — accounts 3663, 1908, 1356 and 1 more: 4 lines in the file
Index Exchange — accounts 192410, 186266, 193336 and 2 more: 5 lines in the file
InMobi — account 6801ebe3b36d4afba25f67b2d0e9d9ed: 1 line in the file, 271 expected lines missing
Ogury — account 77858990-0b64-4485-b9e2-0a660eac712d: 1 line in the file, 17 expected lines missing
OpenX — accounts 537145215, 542511403, 543969731 and 1 more: 4 lines in the file
PubMatic — accounts 158326, 159344, 158126: 3 lines in the file
Sovrn — account 230297: 1 line in the file
TripleLift — accounts 6644, 6732, 6616 and 10 more: 13 lines in the file
Yahoo — account 100031: 1 line in the file

Corrected file: nationalrail.co.uk app-ads.txt (fixed).

FAQ

Does nationalrail.co.uk have an app-ads.txt?

Yes — https://nationalrail.co.uk/app-ads.txt has 165 lines (checked 19 Oct 2026).

Which ad networks does nationalrail.co.uk work with?

Its app-ads.txt lists Google AdMob, Amazon Publisher Services, Magnite (Rubicon), Xandr (Microsoft), Index Exchange, InMobi, Ogury, OpenX, PubMatic, Sovrn, TripleLift, Yahoo.

nationalrail.co.uk app-ads.txt check

Ad networks in nationalrail.co.uk/app-ads.txt

FAQ

Does nationalrail.co.uk have an app-ads.txt?

Which ad networks does nationalrail.co.uk work with?

Is the app-ads.txt of nationalrail.co.uk correct?

Other checked domains

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