SolveNook

Barcode Generator

Generate a static barcode without uploading its contents. Choose Code 128 for printable ASCII text or EAN/UPC for an existing retail identifier, then download a scalable SVG or PNG.

Processed locally. EAN/UPC accept a complete number with a valid check digit, or a number one digit shorter to calculate it. Creating a code does not confer ownership of a retail identifier.

Print at actual size. Do not crop quiet zones.

How the calculation works

Code 128 encodes start, data, checksum and stop symbols. EAN/UPC use alternating weights 1 and 3 from the right of the data digits: check digit = (10 − weighted sum mod 10) mod 10. The encoder validates complete identifiers.

Worked example

EAN-13 data 400638133393 produces check digit 1, giving 4006381333931. Enter either form. Code 128 can encode SOLVENOOK-001 without obtaining a retail identifier.

Assumptions and limitations

Only printable ASCII is accepted for Code 128. EAN-13 accepts 12/13 digits, EAN-8 7/8 and UPC-A 11/12. Black bars on white and 12-module side margins are fixed. Module width is 1–4 pixels. Outputs are static and do not expire or track scans.

Use an identifier allocated to you when trading retail goods. This tool does not register GS1 identifiers, certify print quality or guarantee scanner compatibility. Preserve quiet zones, print at actual size and test the finished label. SVG and PNG processing stay in your browser.

Method reviewed 2026-10-13. Calculation standards · Report an issue