var characterFrequency = function (string) { let tempArray=[...string]; // stores [ 'f', 'u', 'n' ] let finalArray = [] console.log(JSON.stringify(tempArray)+"/"+JSON.stringify(finalArray)) for (var i=0; i<tempArray.length; i++){ //console.log("current letter",tempArray[i]) var found=false; for (var x=0; x<finalArray.length; x++){ console.log(finalArray) //[ <1 empty item>, [ 'f', 1 ], [ 'u', 1 ], [ 'n', 1 ] ] if (tempArray[i] === finalArray[x][0]){ //always fails // if (tempArray[i] == finalArray[x][0]){ //breaks it but seems like the right answer console.log(finalArray[x][1]) finalArray[x][1]+=1 found=true; } } if (!found) { finalArray.push([tempArray[i],1]) } } return finalArray }; console.log(characterFrequency("Testing more letters!"));