JSFiddle - React, Tailwind, and code Playground

JavaScript

let js_images = ["https://picsum.photos/id/1011/650/400", "https://picsum.photos/id/1012/700/400", "https://picsum.photos/id/1013/400/400", "https://picsum.photos/id/1014/600/400", "https://picsum.photos/id/1015/800/400"];
let largeurs = [];
console.log(js_images.length);
for (var i = 0; i < (js_images.length); i++) {
  const img = document.createElement("img");
  const index = i;
  img.src = js_images[i];
  img.onload = function() {
    const largeur = img.naturalWidth;
    console.log(largeur);
    largeurs[index] = largeur;
  }
}

setTimeout(function() {
  console.log(largeurs);
  for (var i = 0; i < (js_images.length); i++) {
    console.log(largeurs[i] + ' Loaded');
  }
}, 500);