Free Online AASA / iOS Universal Links Validator tool icon
AASA • apple-app-site-association • Universal Links

Free Online AASA / iOS Universal Links Validator

Validate Apple App Site Association (AASA): check reachability, Content-Type, JSON structure and applinks rules; includes a Universal Links matcher and a troubleshooting guide.

AASA / iOS Universal Links Validator

Note: Browsers are restricted by CORS, so this tool fetches AASA via a public proxy. Do not input sensitive internal addresses; AASA should be publicly accessible.

Results
AASA source for validation/matching
Paste AASA JSON
Universal Links Matcher
No valid AASA selected
Note: this is rule-level matching only; real iOS behavior is affected by caching, install state, OS version, and entry points.
Tutorial (quick troubleshooting)
1) Deploy AASA (server)
  1. Place the file at `https://<domain>/.well-known/apple-app-site-association` (recommended) or `https://<domain>/apple-app-site-association`.
  2. No extension (no `.json`), HTTPS accessible, and return 200.
  3. `Content-Type: application/json` is recommended (signed AASA may be `application/pkcs7-mime`).
  4. Typical structure: `applinks.apps` is `[]`; `applinks.details` contains `appID` and `paths`/`components`.
2) Configure iOS (client)
  1. In Xcode > Associated Domains, add `applinks:your-domain.com` (include subdomains as needed).
  2. Make sure `appID` is correct: `<TeamID>.<BundleID>` and matches your signing.
  3. Install the app and test by tapping links from Safari/Notes/Messages.
3) Common failure causes
  • Wrong path/filename (missing `.well-known` or mistakenly using `.json`).
  • Redirect/auth/WAF returns HTML.
  • Invalid AASA JSON: missing `applinks.details[].appID` or missing `paths/components`.
  • iOS caching: updates may take time to take effect.
  • Apple CDN may cache: `app-site-association.cdn-apple.com` may not be real-time.
4) Local quick checks (optional)
curl -i https://your-domain.com/.well-known/apple-app-site-association
xcrun simctl openurl booted https://your-domain.com/your/path
Note: commands may vary across macOS/iOS versions; enterprise networks/proxies may affect fetching.

How to Use

  • Enter your App's associated domain (e.g., example.com) in the 'Domain / Site URL' field.
  • Select the AASA source (default .well-known path) and click 'Fetch & Validate'.
  • Check the 'Results' section for HTTP status, Content-Type, and JSON format validity.
  • Use the 'Universal Links Matcher' section to test if a specific URL matches the AASA rules.

Tips

This tool uses a public proxy to fetch files, bypassing browser CORS restrictions.

The AASA file must be accessible via HTTPS and should not have a .json extension.

iOS prioritizes /.well-known/apple-app-site-association for Universal Links validation.

Use the 'Paste manually' mode to validate rules for content that hasn't been deployed yet.

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