We have a 0.2% fee on spot trading, the rest are referral commissions from partner integrations. This is all laid out in the Platform Fees section of our DYOR page.
You can also share this link for convenience, which takes you to the same place: dyor.octo.fi
Take a look at the table, which is also discussed in OIP-17 and please let me know if you have any further questions 😁