Novice Alert** - Ean-13 Help Please . . . フォローする

I'm needing to generate EAN-13 Barcodes for eBay and Website Listings, i've tried the free online one's which is fine when you're doing 1's and 2's, however, i've got 650 products and i'm adding another 400 so i need something that I can keep going back to and editing.

We will add to a certain range of products, lets say we add a red product to a current range of products and I want to ensure the barcode isn't replicated elsewhere and of course, I don't want to have to regenerate barcodes for the whole range of products . . .

Sorry for being a noob, but reaching out for help and advice, which will be gratefully received!!