app-ads.txt / ads.txt Verification

app-ads.txt (for apps) and ads.txt (for websites) are IAB-standard text files that declare which ad exchanges are authorized to sell your inventory. DSPs check these files before bidding — without them, many buyers will not bid on your inventory.

What to add

Add the following line to your file:

praevis.com, {YOUR_PUBLISHER_ID}, DIRECT

Replace {YOUR_PUBLISHER_ID} with the UUID from your supply source (Publisher) settings in the dashboard.

Example:

praevis.com, 3fa85f64-5717-4562-b3fc-2c963f66afa6, DIRECT

Your Publisher ID is found under Supply → click your supply source → Settings → Publisher ID.

Where to put the file

For mobile apps and CTV apps:

The app-ads.txt file lives at your developer domain — the domain listed as your app’s developer in the app store.

iOS: listed under your Apple Developer account domain
Android: listed under your Google Play Store developer domain
CTV / Roku / Fire TV: listed under your developer website domain

URL format: https://yourdeveloper.com/app-ads.txt

The file is checked automatically by DSPs using the app.bundle field in the bid request (e.g., com.yourapp.example → looks up yourdeveloper.com).

Verification process

Praevis automatically verifies your app-ads.txt / ads.txt file every 24 hours. You can also trigger a manual check from the dashboard.

What is checked

File is reachable over HTTPS (200 response, no redirect)
File contains the correct praevis.com, {PUBLISHER_ID}, DIRECT line
Publisher ID in the file matches your registered supply source

How to trigger a manual check

Go to Supply → click your supply source
Under Verification, click Check Now
Status updates within 30 seconds

Verification status

Status	Meaning
Verified	File found, correct line present — DSPs see you as authorised
Pending	First check not yet run (new supply source)
File not found	URL not reachable — check hosting and HTTPS
Line missing	File found but the Praevis line is absent
ID mismatch	Publisher ID in file doesn’t match your registered ID

⚠️

What happens if verification fails? Your supply source still runs auctions, but DSPs with strict app-ads.txt requirements will not bid. This reduces fill rate. Fix the file and re-verify to restore full demand.

Full file example

If you work with multiple exchanges, list them all — one line per exchange. Praevis must be on its own line:

# ads.txt for example.com
# Generated 2026-02-17

# Praevis Exchange
praevis.com, 3fa85f64-5717-4562-b3fc-2c963f66afa6, DIRECT

# Other exchanges (keep yours)
google.com, pub-0000000000000000, DIRECT
appnexus.com, 12345, RESELLER

Troubleshooting

File is verified but fill rate is still low app-ads.txt authorises you — it doesn’t guarantee bids. Check floor price, geo coverage, and pool assignment. → Troubleshooting guide

File returns a 403 or redirect Some CDNs block crawlers by default. Add an exception for IAB verification crawlers (user agent * or by IP whitelist if required by your CDN).

Publisher ID changed Update the line in your file immediately. Old IDs are not accepted.

Dashboard & Metrics Troubleshooting