JSON array javascript

JSon arrays are bounded by [] brackets

try

pets = '[{"name":"jack"},{"name":"john"},{"name":"joe"}]';

also you forgot to use "'s on the last property name.

A simpler JSON array (an array of strings):

["jack", "john", "joe"];

Putting it together as JavaScript:

var pets = '["jack", "john", "joe"]';
var arr = JSON.parse(pets);
console.log(arr[0]); // jack
console.log(arr[1]); // john
console.log(arr[2]); // joe

Your JSON is malformed. Try this:

var pets = '{"pets":[{"name":"jack"},{"name":"john"},{"name":"joe"}]}';
var arr = JSON.parse(pets);
alert(arr.pets[0].name);

yes just change it to this square brackets also check the double quotations on the last element

pets = '[{"name":"jack"},{"name":"john"},{"name":"joe"}]';

var arr = JSON.parse(pets);

alert(arr[0].name);