Free tool
Universal Links & App Links validator
Paste a domain. We'll fetch its iOS apple-app-site-association and Android assetlinks.json and flag the things that silently stop deep links from opening the app.
We fetch /.well-known/apple-app-site-association and /.well-known/assetlinks.json over HTTPS. Nothing is stored.
What this checks
- Wrong Content-Type on the extension-less AASA file
- A 301/302 redirect in front of the file (Apple won't follow it)
- Malformed JSON or a missing applinks.details block
- appIDs that aren't TEAMID.bundle.id, or missing SHA-256 fingerprints
Tired of hand-maintaining these files?
LinkTrail serves verified AASA and assetlinks.json from your own link domain with the correct Content-Type and no redirects, and regenerates them when you add a bundle ID. Set the domain and bundle IDs once.