Go to Catalog/Products and then choose Import/Export. You can use the importer to upload all your variants in one file easily and fast. The supported format of files is CSV.
When you upload the file, you will see a preview of the first 10 variants. There are mandatory fields that you must fill in:
– id– If you are adding a new variant to the shop, this column should be blank, we will create a unique id for every variant. Only exported variants will have an id.
– Price – If the field is left blank the price will be set to 0
– Quantity– If the field is left blank the quantity will be set to 0
– Weight – Can be blank
– Discount Price– Can be blank
– Discount Percentage – Can be blank
– Discount Start at– Can be blank
– Discount End at– Can be blank
– SKU – Can be blank
– EAN-13 – Can be blank
– UPC – Can be blank
– Cost of the item price – Can be blank
– Product name – The name of the product you want to add variants to. It can’t be blank.
– Group 1* – The name of the attribute group. For example ‘Size’. It can’t be blank.
– Attribute 1 – The attribute that refers to Group 1. For example, ‘S’, ‘M’, ‘L’. It can’t be blank.
– Group 2* – The name of the attribute group. For example ‘Color’. It can’t be blank.
– Attribute 2 – The attribute that refers to Group 2. For example, ‘Blue’, ‘Green’, ‘Red’. It can’t be blank.
The number of groups added depends on how many variations your products will have.
All variants to one product must have the same number of unique groups and attributes. For example, if one variant of a product has a group “Size” and ‘Color’, all variants of this product must have the same groups.
If the columns of your file are in a different order, don’t worry. Use the dropdown to change columns’ titles. 
When you are ready click on Import. If no mistakes are made you’ll see a notification saying that the import is successful. If there are mistakes the system won’t upload anything and you’ll see an extra button. Clicking on it you’ll download a file. There you’ll see on which line of the CSV file is the mistake and what exactly it is. 
When you are done editing upload the file again and Import it.
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