I want to send $533 to a company. I have $443.25 in my Coinbase account. And $110.56 balance in my Electrum account. Total of $553.81.

      $553.00
- 533
       $20.81 I believe the BTC transfer fee is around $20.00. How do I determine how much the transfer fees are in both Electrum and Coinbase to calculate or determine I'm sending the guy the correct amount of $533.00?