OAuth Redirect URI Debugger
Find OAuth callback URL mismatches before changing secrets.
Paste the provider dashboard redirect URI, the redirect_uri your app sends, and the error text to find scheme, domain, path, slash, query, localhost, staging, and provider-setting mistakes.
Security note: do not paste client secrets, access tokens, refresh tokens, authorization codes, cookies, or private provider credentials. Redirect URIs and redacted error text are enough for this check.
What this checks: exact redirect URI equality, HTTPS vs HTTP, www vs non-www, callback path, trailing slash, query string, ports, encoding, localhost/staging/production clues, and provider-specific dashboard settings.