JSFiddle - React, Tailwind, and code Playground

HTML

<input type="file">

JavaScript

function getString(a,start,length){
     for(var i=0,v='';i<length;++i) {
      v+=String.fromCharCode(a.getUint8(start+i));
     }
     return v;
    }

    function readID3(){
      var a=new DataView(this.result);
      console.log(getString(a,10,4));
      if(getString(a,0,3)=='ID3'){
       console.log('it has id3 tags');
      };
    }
    function readFile(){
     var a=new FileReader();
     a.onload=readID3;
     a.readAsArrayBuffer(this.files[0]);
    }
    document.getElementsByTagName('input')[0].addEventListener('change',readFile,false);