Google Merchant Center’s 500 × 500 px image minimum from 2027: how to find small images in PrestaShop

From January 31, 2027, Google Merchant Center will require every product image to be at least 500 × 500 pixels, across all product categories and marketing methods. Accounts have been showing “Image too small for upcoming enforcement” warnings since April 2026. In a PrestaShop shop, the problem is rarely the photos themselves – more often it is the thumbnail format the feed sends. Here is how to find every image that is too small, and what to do about it.

What exactly changes

• A 500 × 500 px minimum for image_link and additional_image_link, with no category exceptions.
• Enforcement from January 31, 2027. Until then, Google only warns. You will find the affected products in Merchant Center under “Needs attention”, in the issue history.
• Google will upscale some smaller images itself, and those products will not be disapproved, but they will get a warning. Treat it as a fallback – an image stretched by an algorithm looks worse than the original.
• Google recommends 1500 × 1500 px or more. Files can be up to 16 MB, and supported formats include JPEG, PNG and WebP.

Why in PrestaShop it is usually the thumbnail

PrestaShop stores the original image and generates thumbnails from it in the formats listed in Design › Image Settings: small_default, home_default, large_default and others. A feed module does not send the original to Google, but the URL of one of the thumbnails. In many themes large_default is 800 × 800 px and there is no problem. Sometimes, though, it is 458 px, or the module sends home_default (250 px) – and then every product is too small, even though the originals are 2000 px.

So start by checking which format is in the feed: open the feed XML and look at the URL in g:image_link, for example …/123-large_default/name.jpg.

-- dimensions of product image types
SELECT name, width, height
FROM ps_image_type
WHERE products = 1
ORDER BY width;

If the format used in the feed is below 500 px in either dimension, you have two options: switch the feed to a larger format, or enlarge this format and regenerate thumbnails. Note that changing an existing format’s dimensions also changes how images look in your theme.

How to find originals that are too small

Once the format is large enough, what remains are images whose original is small – often from a supplier import. A thumbnail cannot be sharper than its original: even if the thumbnail file is 800 px, the product on it is small or blurry. Dimensions are not stored in the database, so the files have to be checked. Save this script in the shop’s root directory as check_small_images.php and run it from the command line:

<?php
// php check_small_images.php               – checks the originals
// php check_small_images.php large_default – checks the format sent in the feed
require __DIR__ . '/config/config.inc.php';

$type = $argv[1] ?? '';
$min  = 500;
$rows = Db::getInstance()->executeS(
    'SELECT i.id_image, i.id_product, i.cover
     FROM ' . _DB_PREFIX_ . 'image i
     JOIN ' . _DB_PREFIX_ . 'product p ON p.id_product = i.id_product
     WHERE p.active = 1
     ORDER BY i.id_product, i.position'
);

echo "id_product;id_image;cover;width;height\n";
foreach ($rows as $r) {
    $file = _PS_PROD_IMG_DIR_ . Image::getImgFolderStatic($r['id_image'])
          . $r['id_image'] . ($type !== '' ? '-' . $type : '') . '.jpg';
    $size = is_file($file) ? @getimagesize($file) : false;
    if (!$size || $size[0] < $min || $size[1] < $min) {
        printf("%d;%d;%d;%d;%d\n", $r['id_product'], $r['id_image'],
            $r['cover'], $size[0] ?? 0, $size[1] ?? 0);
    }
}

php check_small_images.php > too_small.csv

Open the result in a spreadsheet. Rows with 0;0 are missing files – those need fixing too. cover = 1 marks the main image, which goes into image_link, so fix those first. The script works on PrestaShop 1.7, 8 and 9. Remove it from the server after use.

Products with no image at all

A product without an image usually gets PrestaShop’s placeholder (“no picture”) in the feed. Google treats placeholders as not allowed, so these products are disapproved regardless of size:

SELECT p.id_product, p.reference
FROM ps_product p
WHERE p.active = 1
  AND NOT EXISTS (SELECT 1 FROM ps_image i WHERE i.id_product = p.id_product);

What to do with the results

1. Feed format too small: switch the feed to a larger format, or enlarge the format and regenerate thumbnails (in batches on a large catalog).
2. Small original, better photo available: ask the supplier for higher-resolution files or take new photos. For 2027, aim for 1500 px.
3. Small original, no better photo: exclude the product from the feed until it is fixed, or let Google upscale it automatically, accepting lower quality.
4. New products: set a minimum image size for whoever adds products and for imports. Otherwise the problem returns within a month.

While you are at it, check the other image rules: no promotional text, watermarks or shop logos overlaid on the image, and the image must show exactly the item being sold.

More on catalog gaps: How to find PrestaShop products with missing images, descriptions or EAN.

Sources

• Google Merchant Center Help – Product data specification update 2026
• Google Merchant Center Help – Image link [image_link]