6 days in Phuket and krabi

We (me and my wife) are coming to Phuket on 22 july.(reach till evening ) Then we have 5 full day and day of departure ( departing on 28 morning/afternoon , flight yet to book ).I am planning for 3 day Phuket and 2 day krabi ( I can catch the flight from krabi) . I want to do day tour on different island ( phi phi must). would it be fine or should I divide it 2 day Phuket or 3 day krabi ?

Phi phi day tour would be better from krabi or Phuket ?