soundcloud-api-auth

Apps & Automation

Implements SoundCloud OAuth 2.1 flows — Authorization Code with PKCE and Client Credentials — including token refresh and secure credential storage. Use when adding login, obtaining tokens, or fixing 401 auth errors.

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SoundCloud API authentication

Endpoints

Purpose	Host
Authorize user	`https://secure.soundcloud.com/authorize`
Token exchange / refresh	`https://secure.soundcloud.com/oauth/token`

Do not use https://api.soundcloud.com/oauth2/token (deprecated).

Authorization Code + PKCE (user-delegated)

Use for /me, uploads, and private user actions.

Generate code_verifier (43–128 chars) and code_challenge = BASE64URL(SHA256(verifier))
Redirect user to authorize URL with response_type=code, client_id, redirect_uri, code_challenge, code_challenge_method=S256, state
Exchange code at token endpoint with grant_type=authorization_code, code_verifier, redirect_uri
Store access_token, refresh_token, expires_in securely (server-side or httpOnly cookie — never in client-visible storage for secrets)

Client Credentials (public resources only)

curl -X POST "https://secure.soundcloud.com/oauth/token" \
  -H "Content-Type: application/x-www-form-urlencoded" \
  -H "Authorization: Basic BASE64_CLIENT_ID_SECRET" \
  --data-urlencode "grant_type=client_credentials"

Refresh (single-use refresh tokens)

curl -X POST "https://secure.soundcloud.com/oauth/token" \
  -H "Content-Type: application/x-www-form-urlencoded" \
  --data-urlencode "grant_type=refresh_token" \
  --data-urlencode "refresh_token=REFRESH_TOKEN" \
  --data-urlencode "client_id=CLIENT_ID" \
  --data-urlencode "client_secret=CLIENT_SECRET"

After refresh, discard the old refresh token; the response includes a new one.

Constraints

Access token lifetime ~1 hour
Refresh tokens are single-use — persist the new refresh token from each response
Avoid hammering client_credentials — cache access token and refresh instead
Register redirect URIs at https://soundcloud.com/you/apps/

Reference

Full flow details: https://developers.soundcloud.com/docs/api/guide#authentication