About FreeBarcodeGenerator.app
FreeBarcodeGenerator.app is a barcode-image tool with guidance for choosing and checking common formats. Its purpose is to help you represent an existing value clearly, not to manufacture a product identity.
Image generation has a limited job
A barcode generator converts data into a symbol. It does not issue GS1 identifiers, allocate ISBNs, register stock in a retailer's database or certify printed labels. Acceptance depends on the receiving system and the quality of the physical output.
This site is not GS1 or an ISBN agency. Links to standards and official guidance do not imply endorsement or certification.
Sources you can check
The EAN/UPC and GS1-128 explanations refer to the GS1 General Specifications. Code 128 and Code 39 have their own ISO/IEC symbology specifications. Book-number guidance follows the International ISBN Agency.
Guides distinguish between a format's capabilities and a feature actually offered by this tool. A valid checksum is not proof that a product number is allocated correctly, and a successful scan is not a formal verification report.
Report an unclear rule or unexpected result
Use the contact page to report an input error, export issue or confusing explanation. A made-up internal identifier is usually enough to reproduce a problem; do not send customer databases or commercially sensitive label lists.
Content references reviewed: November 6, 2026.
Method and transparency
Last updated: 6 November 2026. Local technical preview only.