Array reduzieren und zählen basierend auf Proeperty JS
const array = [
{id: 12, name: 'toto'},
{id: 12, name: 'toto'},
{id: 42, name: 'tutu'},
{id: 12, name: 'toto'},
];
const id = 12;
const count = array.filter((obj) => obj.id === id).length;
console.log(count);
Horrible Hornet