sum all the same key values in array of objects code example
Example: javascript sum array values by key
var array = [
{name: "Peter", age: 43},
{name: "John", age: 32},
{name: "Jake", age: 21}
];
array.reduce(function(sum, current) {
return sum + current.age;
}, 0); // 43 + 32 + 21 = 96