A Global Trade Item Number (GTIN) is a barcode assigned to each product variant. For example, if t-shirts come in three sizes (small, medium, large) and two colors (black and white), all 5 variants must have unique GTINs.

There are four types of GTIN: EAN/UCC-8, UCC-12, EAN-13, ITF-14.

Where to find a GTIN?

Trademark owners or manufacturers can assign barcodes. If you are a brand owner or manufacturer, you will need to register with GS1 CN to get unlimited encoding of your products. Otherwise, you’ll have to request a trademark owner or manufacturer to provide you with the barcodes of the product you’re planning to sell.

How to Apply for GTIN?

If you’re a trademark owner or manufacturer, and you’re going to sell a new product, you’ll need to get a GTIN. So, to apply for it, please do the following:

1. Go to the GS1 website.
2. Log in or sign up on the site.
3. Provide the necessary information.
4. Follow the instructions to apply for barcodes.

How to check the GTIN validity?

1. Open the GS1 digit calculator.
2. Copy your GTIN without the last digit, paste it into the calculator and click Calculate.
3. The calculator will show you the last digit of your GTIN.
4. Compare it with the last digit of your actual GTIN. If the last digits of the GTINs match, then your GTIN is valid.

If you received the barcode not through GS1 website, then please contact them.

What are the requirements for GTIN on Joom?

• It’s forbidden to use false GTIN.
• GTINs cannot be removed, only modified. 
• Each GTIN can only be assigned to one product variant. It is forbidden to reuse GTIN.
• If your product belongs to a specific category (handmade, collectible, etc.), and you're uncertain whether you should apply for GTIN, please contact GS1 for assistance.
• We accept GTINs with 8, 12, 13, and 14 digits.

How to add a GTIN code on Joom?

There are three ways to add a GTIN code to a product variant on Joom. You can do it via Merchant Panel, CSV file or Joom API.

Merchant Panel UI

1. Go to the Products page in the Merchant panel.
2. Choose a product you want to edit. Use product filters to find the specific products.
3. Click Edit Product.
4. Scroll down to Product Variation and fill in the GTIN code for a corresponding variant.
5. Click Save.

CSV file

Please refer to the article How to Edit Products.

Joom API

Please check the related guide in the Joom API documentation.

Would it be possible to change a GTIN?

It is usually impossible to assign a new GTIN to a product. But if the product's characteristics are significantly changed (e.g., a chemical formula of a cream has changed, or a component has been added to the composition), then a new GTIN can be assigned.