QQudo Outils

Barcode Generator

Generate Code 128, Code 39, EAN-13, EAN-8, UPC-A and ITF-14 barcodes. All processing happens in your browser.

Barcode content is processed in your browser. Nothing is uploaded to Qudo servers.

This tool only generates barcode graphics from your input. It does not assign valid GTIN, EAN, UPC, ISBN or other official product codes.

For retail product use, official barcodes must be obtained from authorized numbering organizations. A self-generated EAN or UPC number is not a legally assigned product code.

Characters: 0Checksum: No

Size Settings

Barcodes need blank space on left and right for scanning.

Color Settings

Preview

Enter content to preview

Keyboard Shortcuts
Ctrl+Enter: Generate barcodeCtrl+S: Download PNG

Barcode Generator Tool

Generate Code 128, Code 39, EAN-13, EAN-8, UPC-A, ITF-14 and Codabar barcodes. Supports single and batch generation with PNG and SVG download. All processing happens locally in your browser.

How to Use

  1. Select barcode type based on your needs.
  2. Enter the content to encode.
  3. Adjust size, colors and text settings if needed.
  4. Check the checksum and scan verification status.
  5. Download as PNG or SVG, or generate batch results.

Code 128 vs Code 39

Code 128 has higher encoding density and supports full ASCII characters. Code 39 has a more limited character set but is widely supported by older scanners. Choose based on your scanning equipment and business system requirements.

Checksum Digits

EAN, UPC and ITF barcodes include a checksum digit calculated from the other digits. This helps detect data entry or scanning errors. The checksum is not encryption or anti-counterfeiting.

What is Quiet Zone

The quiet zone is the blank space on the left and right sides of a barcode. Scanners need this space to properly detect and read the barcode. Insufficient quiet zone is a common cause of scanning failures.

About Product Codes

This tool generates barcode graphics from your input. It does not assign valid GTIN, EAN, UPC or ISBN numbers. For retail products, official barcodes must be obtained from GS1 or authorized numbering organizations in your country.

SVG vs PNG

SVG is vector format that scales without quality loss, ideal for printing and design software. PNG is raster format suitable for everyday use, documents and web. Low-resolution PNG may appear blurry when enlarged.

Common Use Cases

  • Inventory and asset tracking labels
  • Warehouse and logistics management
  • Internal production tracking
  • Shipping carton labels (ITF-14)
  • Library and archive management
  • Product labeling for internal use
  • Batch serial number generation
  • Book and publication display codes

Data & Privacy

All barcode generation happens entirely in your browser. Content is never uploaded to any server. File names are not sent to analytics services. Refreshing or closing the page releases all data from memory.

Limitations

1D barcodes have limited data capacity compared to QR codes. Chinese characters are not supported in 1D formats. Scanning success depends on print quality, size, colors, quiet zone and scanner capabilities. Maximum 500 barcodes per batch.

Frequently Asked Questions

Is barcode content uploaded to a server?▼
No. All barcode generation happens locally in your browser. Nothing is uploaded.
What is the difference between Code 128 and Code 39?▼
Code 128 supports full ASCII and has higher density. Code 39 is limited to uppercase letters, numbers and some symbols. Choose based on your scanner compatibility.
Why does EAN-13 need a checksum?▼
The checksum digit helps detect data entry and scanning errors. It is calculated from the other digits using a standard formula.
Can this tool assign valid product barcodes?▼
No. This tool only generates barcode graphics. Official GTIN/EAN/UPC numbers must be obtained from GS1 or authorized organizations.
Why can't my barcode be scanned?▼
Check the module width, quiet zone, color contrast and print quality. Low contrast or insufficient quiet zone are common causes of scanning failures.
Can I use colored barcodes?▼
Yes, but ensure high contrast between bars and background. Dark bars on light background works best. Avoid light-colored bars.
Why do barcodes need blank space on the sides?▼
The quiet zone helps scanners detect the start and end of the barcode. Without it, scanning may fail or produce incorrect results.
Should I use PNG or SVG?▼
SVG is better for printing and design work as it scales without quality loss. PNG is better for everyday use, documents and web.
Can I generate serial numbers in batch?▼
Yes. Use the serial number generator with prefix, start/end numbers, step and digit padding settings.
Does this support Chinese characters?▼
1D barcodes do not support Chinese. For Chinese content, use the QR Code Generator instead.
Can I generate ISBN barcodes?▼
This tool can generate the barcode graphic from an ISBN number, but cannot assign valid ISBN numbers. ISBNs must be obtained from authorized agencies.
Why does 13-digit EAN show checksum error?▼
If you enter 13 digits, the tool verifies the last digit against the calculated checksum. If they don't match, it shows an error.
How do I print clear barcodes?▼
Use high contrast (black on white), adequate module width (2px or more), standard quiet zone, and output at 2x or higher scale for printing.
Can I download all barcodes at once?▼
Yes. After batch generation, click Download All to get a ZIP file containing all barcodes and a manifest CSV.

Barcode content is processed in your browser. Nothing is uploaded to Qudo servers.