GS1-128 Barcode Generator

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GS1-128 Barcode Generator

Our GS1-128 Barcode Generator enables you to create structured barcodes that encode detailed product information, including GTINs, batch numbers, and expiration dates. Generate barcodes for commercial use and download them in PDF, PNG, SVG, or JPG formats. Learn about barcode dimensions, data formatting, and checksum calculation, and explore applications in logistics, healthcare, and inventory management to streamline your operations effectively.

What Is the Ideal Size for a GS1-128 Barcode?

Ideal Size of GS1-128 Barcode

The GS1 General Specifications outline the dimensions for GS1-128 barcodes to ensure reliable scanning and compliance.

Dimensions:

  • X-dimension (Width of the Narrowest Bar): 0.495 mm (recommended).

  • Bar Height: Minimum 31.75 mm.

  • Maximum Length: Must not exceed 165 mm, including Quiet Zones.

Magnification Range:

GS1-128 barcodes can be scaled from 25% to 100% magnification based on requirements:

  • 25% Magnification:

    • X-dimension: 0.25 mm

    • Bar Height: 13 mm

    • Quiet Zone: 2.54 mm

  • 100% Magnification:

    • X-dimension: 1.02 mm

    • Bar Height: 32 mm

    • Quiet Zone: 10.16 mm

Quiet Zones:

The blank areas on either side of the barcode, called Quiet Zones, are critical for scanning. Their width must be at least 10 times the X-dimension. At the standard X-dimension of 0.495 mm, this equates to a Quiet Zone of 4.95 mm on both sides.

How To Use Our Free GS1-128 Barcode Generator?

Use of
Our Free GS1-128 barcode generator

Using our free GS1-128 barcode generator is straightforward. Just enter your desired barcode data, including Application Identifiers (AIs) and their corresponding values, ensuring compliance with GS1 standards. Once your data is set, click “Generate GS1-128 Barcode.”

The barcode will be instantly created, and you can download the barcode images in various formats such as PDF, SVG, PNG, or JPG, making it easy to integrate into your digital and print needs. Suitable for professional and commercial applications, this tool offers secure, high-quality outputs for immediate use.

How is the Checksum Calculated for GS1-128 Barcodes?

Checksum Calculated for GS1-128 Barcodes

Here’s how to calculate it step by step, explained simply:

  1. Assign Numeric Values
    Each character in the barcode, including the start code, is assigned a numeric value based on the Code 128 character set. The start code (e.g., Code A, Code B, or Code C) must be included in the calculation.

  2. Apply Weights and Find the Total Sum
    Start from the rightmost character (not including the stop character) and assign weights starting at 1, increasing by 1 for each character as you move left. Multiply each character’s numeric value by its weight and add up all the results, including the start code.

  3. Calculate the Checksum
    Divide the total sum by 103. The remainder of this division is the checksum value. If the remainder is 0, the checksum value is also 0.

  4. Find the Checksum Character
    The checksum value corresponds to a character in the Code 128 character set. Add this character to the barcode to complete it.

Let’s look at an example to understand this better:

Suppose the barcode data is “(01)95012345678903”, and the start code is Code C (numeric value = 105).

  1. Assign Numeric Values
    Using the Code 128 character set:

    • Start Code C = 105

    • ( = [Correct Value], 0 = 16, 1 = 17, 9 = 25, 5 = 21, 0 = 16, 1 = 17, 2 = 18, 3 = 19, 4 = 20, 5 = 21, 6 = 22, 7 = 23, 8 = 24, 9 = 25, 0 = 16, 3 = 19

  2. Apply Weights and Add Up the Results
    Multiply each value by its weight and add them up:
    (105 × 1) + ([Value for (] × 2) + (16 × 3) + (17 × 4) + (25 × 5) + … = Total Sum

  3. Calculate the Checksum
    Divide the total sum by 103 and take the remainder. For example, if the total sum is 910, the remainder is 83.

  4. Find the Checksum Character
    Look up the checksum value (83) in the Code 128 character set to find the corresponding character. Add this character to the end of the barcode.

What is the Character Limit of Your GS1-128 Barcode Generator?

Character Limit of Your GS1-128 Barcode

Our GS1-128 barcode generator supports up to 48 characters, including Application Identifiers (AIs) and their associated values. This practical limit ensures barcodes remain scannable and fit within typical size and resolution constraints.

While GS1-128 barcodes do not have a fixed character limit, their capacity depends on factors such as the physical barcode size, the X-dimension (narrowest bar width), printing resolution, and scanner capabilities. Properly structuring data with AIs and separators is essential for compliance with GS1 standards and ensuring readability across logistics and supply chain applications.

Where is the GS1-128 Barcode Used?

The GS1-128 barcode is widely used in logistics, retail, and healthcare for tracking shipments, managing inventory, and ensuring product traceability.

It is essential in sectors like food and pharmaceuticals for encoding batch numbers, expiration dates, and regulatory data. This barcode symbology is favored for its ability to encode detailed, structured information while maintaining compatibility with global supply chain standards.

Troubleshooting GS1-128 Barcode Issues

GS1-128 barcodes are essential in supply chain and logistics operations, but challenges can occur during printing, scanning, or data encoding. Here’s how to address common problems effectively:

Print Quality and Contrast

Poor print quality or low contrast between bars and spaces can hinder scanner readability. To address this, use high-resolution printers (300 dpi or higher) and ensure sufficient contrast between the bars and background. Regularly clean printer components, such as printheads and rollers, to maintain output quality.

Quiet Zone Violations

Insufficient quiet zones, the blank spaces around the barcode, can cause scanning errors. Ensuring quiet zones are at least 10 times the X-dimension (the width of the narrowest bar) resolves this issue. For instance, with an X-dimension of 0.495 mm, the quiet zone should be 4.95 mm on both sides.

Incorrect Data Formatting

Data that is not structured according to GS1 standards results in invalid or unreadable barcodes. Using GS1-compliant generators and ensuring Application Identifiers (AIs) are correctly encoded helps prevent this problem. Always validate data structure with GS1 standards before printing.

Scanner Compatibility

Barcodes may fail to be interpreted correctly if scanners are not configured to read GS1-128 barcodes. Ensure that the scanner supports GS1-128 and update its firmware or settings if necessary. Enabling the GS1-128 symbology in the scanner’s configuration is also essential.

Scaling Issues

Barcodes that are printed too small or too large can be unreadable by scanners. To prevent this, ensure barcodes are printed within the recommended magnification range of 25% to 100%. For example, the X-dimension should fall between 0.25 mm and 1.02 mm.

Physical Damage

Scratched, smudged, or otherwise damaged barcodes can lead to scanning failures. Protecting barcodes with laminates or using durable materials suitable for the environment mitigates this risk. Avoid placing labels in areas prone to wear or exposure to harsh conditions.

Overcrowded Data

Encoding excessive information into a single barcode reduces clarity and increases density. Splitting data across multiple barcodes when necessary and avoiding exceeding the maximum character limit of 48 ensures better readability.

Environmental Factors

External factors such as glare, dirt, or extreme temperatures can affect scanning accuracy. Placing barcodes in protected locations and ensuring proper lighting conditions for scanning is vital. Regularly cleaning the barcode surface also helps maintain readability.

Which Scanners are Compatible with GS1-128 Barcodes?

Most 1D barcode scanners, including laser, CCD, and high-resolution imaging scanners, are compatible with GS1-128 barcodes. Laser scanners are versatile and can read at various angles and distances, making them ideal for logistics, warehousing, and retail applications.

CCD scanners are well-suited for close-range scanning in well-lit environments and are commonly used in point-of-sale systems. High-resolution imaging scanners excel at reading dense and long GS1-128 barcodes, even when printed on curved or small surfaces.

However, basic pen-style scanners may struggle with the complexity and length of GS1-128 barcodes. Additionally, some 2D barcode scanners may require specific programming to support GS1-128 formats. Ensuring your scanner is GS1-compliant will guarantee accurate and efficient barcode reading.

Is there a Scan Limit to the GS1-128 Barcode Generated Using your Online Barcode Generator?

There is no scan limit for the GS1-128 barcode generated using an online barcode generator. Once created, the barcode can be scanned unlimited times, provided it meets quality standards and is printed or displayed clearly. This ensures it works consistently across various POS systems and scanning devices.

Do You Have Other Barcode Generators?

Yes, we offer a variety of barcode generators to meet your needs. Beyond the GS1-128 barcode, you can create EAN barcodes, QR code, Universal Product Codes (UPC), and Code 128 or Code 39 barcodes. We also provide options for ITF, EAN-13, Data Matrix, and GS1 Databar.

For specialised needs, you can generate Aztec code, Maxicode, and PDF417 barcodes. All barcode types can be customised, downloaded as images, and are suitable for various business applications.

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