Free deep linking tools
Short answer
Four free tools, no login and no signup: an AASA & assetlinks.json generator for setting up Universal Links and App Links, a deep link debugger for working out why an existing setup fails, a Firebase Dynamic Links migration checker for teams moving off FDL, and a UTM builder for tagging campaign URLs. All four run in the browser and none require an account.
AASA & assetlinks.json Generator
Generate a valid apple-app-site-association file for iOS Universal Links and an assetlinks.json for Android App Links. Runs entirely in your browser — paste your team ID, bundle ID, package name, and SHA-256 fingerprint, and get syntax-highlighted output plus a hosting guide.
Use it when: Setting up deep linking on a new domain.
Deep Link Debugger
Check whether a live domain is correctly configured for Universal Links and Android App Links. Fetches the association files, validates their structure and content type, and reports exactly which step is failing.
Use it when: Your links open Safari or Chrome instead of the app.
Universal Link Tester
Paste your apple-app-site-association file and a list of URLs to see which open the app and which fall through to Safari. Applies Apple's real matching rules — path, query and fragment patterns, wildcards, case sensitivity and exclude flags — and names the rule that decided each outcome, including later rules shadowed by an earlier catch-all.
Use it when: Your AASA file is served correctly but the wrong URLs open the app.
SKAdNetwork Conversion Value Builder
Design a conversion value schema inside the 64 slots a SKAdNetwork postback actually carries. Map revenue buckets or funnel steps to fine values 0–63, assign the SKAN 4 coarse low/medium/high fallback, and export JSON, CSV and Swift for both SKAdNetwork and AdAttributionKit.
Use it when: Deciding what your iOS postbacks should measure, before you ship.
Firebase Dynamic Links Migration Checker
Paste a page.link URL to see what it was configured to do, and get the equivalent Deeplinkly link configuration. Firebase Dynamic Links shut down on 25 August 2025 and every page.link URL has stopped resolving.
Use it when: Migrating off Firebase Dynamic Links.
UTM Builder
Build trackable campaign URLs for ads, social and email. Fill in source, medium, campaign, term and content — or use a one-click channel preset — and get a live preview, a copy button that warns on missing parameters, and a downloadable QR code.
Use it when: Tagging a campaign so analytics can attribute the traffic.
New to deep linking? Start with what deep linking is and how deferred deep linking works.