Set up a sheet
- Set column A to Plain text before entering codes such as
BOX-0042so leading zeros survive. - In B2 enter
="*"&UPPER(A2)&"*", then fill down. Choose the Libre Barcode 39 font in the font picker if your Sheets account offers it; availability can vary. - Reject non-Latin characters and symbols outside
A-Z 0-9 - . space $ / + %. Print and scan a real proof at 100%.
For BOX-0042, the formula yields *BOX-0042*. The asterisks delimit the barcode, and the scanner reads BOX-0042. This site does not send sheet contents to an IMAGE URL or request access to Google Sheets.