Email Exist Check after input field is not focus

Hi guys, I just want to ask is anyone here already do a email exist validationafter the input email field is not focus? Can you help me or give me some tips on how to do that? I already have a rest api for cheking the existing emails but don’t know how to implement it in an input field using http request… I just know ng-blur but everytime I focus the input and out of focus the email checker always run… Thanks…