[Aetae]

new Promise((resolve, reject) => {
  var img = new Image();
  img.onload = () => resolve(img);
  img.onerror = reject;
  img.src - '/upload/' + data['name'];
}).then(
  naturalWidth => {
    $('.tech').append("<img src='/upload/" + data['name'] + "' class='" + data['id'] + " toimg'><p class='psize'></p></div>");
    $('.psize').append(naturalWidth);
  },
  error => {
    //картинка не загрузилась
  }
)