Follow these steps to get your sp_dc cookie value.
- Install Cookie-Editor for your browser (Chrome / Firefox / Edge / Safari).
- Open spotify.com and log in to the account you want to upgrade.
- Click the Cookie-Editor icon, search
sp_dc, then copy its value.
- Paste it into the field above.
Value usually starts with AQA... and is ~100–200 characters.
Sent over HTTPS, never stored after the upgrade completes.