João Carmo Pereira

This plugin adds a numeric GTIN field to Simple Products and Product Variations if they exist. This field can be used on product pages and for product feeds through shortcode. 
Additionally, the plugin provides an options menu where users can delete all GTIN entries from the database before uninstalling the plugin.

Carmo Product GTIN for WooCommerce

This plugin will add a numeric GTIN field to Simple Products and Product Variation if they exist.  This field can be used via shortcode [carmogtin] on …

Dmitry V. (CEO of "UKR Solution")

<h3>Generate or Import UPC/EAN/GTIN codes from CSV/Spreadsheet file into WooCommerce products.</h3>
<iframe loading="lazy" title="EAN/UPC (GTIN) Generator and Importer from Excel/CSV file (GS1) for WooCommerce/WordPress" width="750" height="422" src="https://www.youtube.com/embed/i0C0e0lRRtQ?feature=oembed" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe>
This plugin was designed to achieve 2 major purposes:
<ol>
<li>
Assign codes for all your existing products automatically. 
So, you don’t have to open each WooCommerce product and add the UPC/EAN code manually.
</li>
<li>
Assign codes for newly created products. 
So, when you create a new product – the code will be added to the product automatically.
</li>
</ol>
In plugin settings you will need to specify barcode type (EAN or UPC) and the product field where to store the code.
UPC is used in USA and contains 12 digits. 
EAN is used wordlwide and contains 13 digits.
You can generate codes into product SKU field or into any other product field as plugin integrated with serveral barcode plugins. 
Also you can specify custom field name to use any other product field for UPC/EAN generation.
After you selected required code type, save the settings and then press “Assign codes” button. 
In opened popup you will see progress how much products were processed. 
As soon as codes are generated you can close the window and check your products for generated UPC/EAN codes.
For the new products UPC/EAN barcode will be generated automatically as soon as you save/publish the product.
Generated codes are valid (have correct the last checkum digit) and ready for using in barcode generation tools.
However, from legal point of view free UPC/EAN codes should be used only internaly (inside your website/company).
<a href="https://www.ukrsolution.com/WordPress/UPC-EAN-code-importer-and-generator" rel="nofollow ugc">Read more</a> about diferences between free and paid UPC/EAN codes.
PRO Version: Allows to import UPC/EAN codes from the purchased Excel or CSV file.
Contact <a href="https://www.ukrsolution.com/" rel="nofollow ugc">UKR Solution</a> team if you have any questions.

UPC/EAN/GTIN Barcode Generator/Importer

Generate UPC/EAN/GTIN codes or import them from CSV/Spreadsheet file into WooCommerce products

Carmo Product GTIN for WooCommerce vs UPC/EAN/GTIN Barcode Generator/Importer