Barcode Tools
Code 128 Barcode Generator
Generate Code 128 barcodes from any printable ASCII text. Widely used in shipping, logistics and inventory systems. Adjust bar width, height, and margins, then download as PNG or SVG.
Supports all printable ASCII characters (space through ~). No limit on length.
🔒 All processing happens locally in your browser. No data is uploaded.
Code 128 Symbology Architecture & ISO/IEC 15417 Standards
Code 128 is an extremely high-density linear barcode symbology defined under international standard ISO/IEC 15417. Unlike numeric-only retail barcodes like UPC-A and EAN-13, Code 128 can encode all 128 ASCII characters (including uppercase, lowercase, punctuation, numbers, and control codes) using three distinct code sets (A, B, and C).
Character Sets & Auto-Switching
Code Set A: Uppercase letters, digits, and ASCII control characters (00–95).
Code Set B: Full printable ASCII (uppercase, lowercase, digits, and punctuation).
Code Set C: Numeric double-density encoding (00–99 encoded into single bar patterns), halving the required physical width for digit sequences.
Modulo 103 Checksum & Quiet Zones
Data integrity is enforced through a mandatory weighted modulo-103 check character calculated automatically before transmission. For reliable scanning by laser and CCD readers, a minimum quiet zone of 10 times the module width (X-dimension) is maintained on both margins.
Code 128 Barcode Frequently Asked Questions
What is Code 128 used for?
Code 128 is the global standard for logistics, shipping containers (GS1-128 / UCC-128), carton labels, pharmaceutical tracking, and enterprise asset inventory management.
Does Code 128 need a manual check digit?
No. The modulo-103 checksum is calculated automatically by the browser generator and appended to the symbol structure.
What is the difference between Code 128 and Code 39?
Code 128 is significantly more compact, supports lowercase letters, and includes mandatory checksum verification. Code 39 has a larger physical footprint and is primarily used in legacy industrial equipment.
Are generated barcodes stored on your servers?
No. Barcodes are rendered entirely in client-side memory using HTML5 Canvas and SVG. No data is transmitted to or logged on remote servers.
1D Barcode Symbologies & Scanning Standards
Linear 1D barcodes encode alphanumeric data using alternating parallel lines and spaces with standardized width ratios. Choosing the appropriate symbology-such as Code 128 for variable-length logistics labels, EAN-13 for global retail products, or UPC-A for North American point-of-sale systems-ensures seamless optical recognition across laser scanners, CCD readers, and camera-based mobile apps.
Quiet Zones & Contrast
Maintain a solid unprinted margin (the quiet zone) of at least 10 times the narrowest bar width on both ends. Ensure high optical contrast-dark bars on a clean white background-to prevent scanner read failures under warehouse and retail lighting.
Vector Print & Privacy Security
Export your finished code in SVG vector format for crisp, infinite scalability on large signage, product packaging, and business cards without pixelation. All generation and camera decoding executes 100% locally in your browser memory-no private credentials, URLs, or scans are ever uploaded to a server.
Additional Technical FAQs
What is the minimum recommended print size for reliable scanning?
For standard smartphone camera scanning at close range (0.3–0.5 meters), print QR codes at a minimum size of 2 x 2 cm (0.8 x 0.8 inches). For posters and billboards, use a 10:1 distance-to-size ratio (e.g., a code scanned from 2 meters away should be at least 20 cm wide).
Are generated codes permanent, and do they ever expire?
All codes generated on BeYourTools are static and permanent. The encoded data (such as your URL, text, or barcode number) is directly baked into the graphical modules with zero server redirection, meaning they will function forever without expiration.