OAuth URL Builder

Construct an OAuth authorization URL from your provider settings. PKCE parameters are included only when code_challenge is set. Prefer response_type=code; implicit flow (token) is deprecated. Add extra key=value parameters in the input if needed.

  • Runs entirely in your browser
  • No data stored or sent to a server
  • Free forever — no signup
  • Instant conversion

Input and Output

Use the interactive encoder and decoder on this page to process your text.

Learn more about OAuth URLs

Building OAuth 2.0 Authorization URLs

OAuth URL Building

Required Parameters

Most OAuth 2.0 authorization code flows need client_id, redirect_uri, response_type=code, and optionally scope, state, and PKCE parameters.

Real-World Examples

https://auth.example.com/authorize?client_id=...&redirect_uri=...&response_type=code&scope=openid+profile

Add state to prevent CSRF on the callback

Add code_challenge and code_challenge_method=S256 for PKCE

Common Mistakes

  • Redirect URI mismatch — must exactly match a registered callback URL
  • Omitting state — exposes the flow to CSRF attacks
  • Using implicit flow (response_type=token) for new apps — prefer authorization code with PKCE

Developer Tips

  • Generate PKCE values with the PKCE Generator tool on this site
  • URL-encode parameter values — use the URL Encoder for individual values
  • Log the full authorize URL during local debugging, redact in production logs

Frequently asked questions

Where do I get code_challenge values?

Use the PKCE Generator tool on this site to create code_verifier and code_challenge pairs.

Why does my redirect fail with redirect_uri_mismatch?

The redirect_uri parameter must exactly match one of the URIs registered with your OAuth provider, including trailing slashes and scheme.

What is the state parameter for?

State is a random value you store in session and verify on callback. It prevents cross-site request forgery during OAuth.