Will my bar code work with Amazon, eBay, Google, etc.?
Yes, the GTIN’s (UPC’s/EAN’s) that we provide will work with their systems, as well as just about every other store on Earth. All retail P.O.S. systems globally use GS1's UPC & EAN formats for retail product identification. This is the known global standard, these standards were created in the 70's by the UCC, now known as GS1.
All of our GTIN's are from GS1-USA and specifically from before 2002, which is how you can legally own them and use them as you desire. Some stores may have arbitrary "invented" rules and you would need to check with the store first to make sure they follow the standards that GS1 operates on.
A note on Amazon:
We, as well as many thousands of Amazon sellers have clarified with Amazon’s seller support that their GTIN requirements have not changed and that sellers (you) are allowed to own your own GTIN's as long as they are legal.
We believe their recent communications have been to threaten those less-than-honest sellers whom try to defraud Amazon’s open (trust based) system by guessing or stealing other’s GTIN’s on purpose. *Using a company's GTIN without express permission is illegal. This does not apply if a seller is trying to create a listing based on an item that already exists in the market, aka "piggy backing" which was created & promoted by Amazon.
As of mid March (2018) it is looking like the only amazon-specific seller program that newly requires renting/licensing GTIN's (meaning you cannot buy/own your own GTIN's and use them on amazon) is amazon's newly revamped Brand-Registered-Program. This very small seller group is forced to rent codes annually from GS1 directly. We believe this is due to amazon joining the board of directors of GS1 in 2016.
Also, due to Amazon enforcing branding restrictions, you will need to know Amazon's policies regarding GTIN's & the brands that they belong to. For example: When selling a Nike shoe, Amazon wants you to use Nike's UPC number specific to that shoe's model #, and not your own UPC number. Another example would be if you were creating a bundle of 5 Nike Shoes, since Nike does not sell bundles, you could then use your own UPC number but would not be able to use Nike's name in the title of the listing since you are not Nike. Visit amazon's Seller-Central-Forums for further education on their unique listing requirements.