MSI Barcode Generator
Create an MSI Plessey barcode for inventory marking.
How to use the MSI Barcode Generator
- Enter a number (digits only).
- Download the barcode as PNG.
About the MSI Barcode Generator
MSI — also called MSI Plessey — is a numeric-only barcode used mainly for inventory and shelf labels in retail. That is its niche: marking bin locations, shelf edges and racking, where the code identifies a place rather than a product. It encodes digits only, and it is not particularly dense — fine for the short location numbers it typically carries.
The important detail is check digits. MSI has several optional schemes — mod 10, mod 11 and doubled variants — and different systems expect different ones. This tool encodes exactly the digits you enter and adds no check digit. If the system reading your labels expects one, calculate it and include it in the number yourself, otherwise the label will scan and then be rejected as invalid. That mismatch is by far the most common problem people hit with MSI.
Keep the value short — every digit widens the symbol, and shelf labels are rarely generous with space — print with good contrast, and leave the quiet zones clear. MSI is a legacy format with narrower scanner support than the mainstream alternatives; for anything new, Code 128 is denser, handles letters and is read by essentially everything.
Frequently asked questions
What can MSI encode?
Digits only, 0 to 9. There is no provision for letters or symbols, which is why it is limited to numeric inventory and location codes.
Does this tool add a check digit?
No. It encodes exactly the digits you enter. MSI has several optional schemes — mod 10, mod 11 and doubled variants — and only your system knows which it expects, so calculate it there and include it in the number.
Where is MSI actually used?
Chiefly inventory control and shelf marking in retail and warehousing — labelling bin locations and racking rather than products themselves.
Should I use MSI or Code 128?
Code 128 for anything new: it is denser, encodes letters as well as digits, includes its own check character and is read by virtually every scanner. Choose MSI only when an existing system requires it.
Will every scanner read an MSI barcode?
Not automatically. MSI is a legacy format and many scanners ship with it disabled, so it often has to be switched on in the scanner configuration. Test with your actual hardware before printing a batch.