What percent does apple take out when transferring instantly to bank?

In this support article→Transfer money in Apple Cash to your bank account or debit card - Apple Support

Footnote 2: A 1.5 percent fee (with a minimum fee of $0.25 and a maximum fee of $15) is deducted from the amount of each Instant Transfer.

Note that you can only do an instant transfer to a debit card, not directly to the bank.