Barcode Generator

What is a Barcode?

A barcode is a machine-readable representation of data that uses varying widths and spacings of parallel lines (in one-dimensional barcodes) or geometric patterns (in two-dimensional barcodes) to encode information. Barcodes were first patented in 1952 and have since become an indispensable tool in retail, manufacturing, logistics, healthcare, and virtually every industry that requires efficient data tracking and identification.

The fundamental principle behind barcode technology is simple: a light source illuminates the barcode, and a sensor detects the reflected light. Dark bars absorb light while light spaces reflect it, creating a pattern of high and low signals that the scanner converts into digital data. This data is then used to look up product information, track inventory, process transactions, and perform countless other automated tasks.

Our Barcode Generator tool allows you to create barcodes in multiple formats directly in your web browser. Simply enter your data, select the barcode format that suits your needs, and download the generated barcode as a PNG image. The entire process is free, fast, and requires no software installation.

Types of Barcodes

There are many different barcode formats, each designed for specific use cases and data requirements. Our generator supports the six most widely used one-dimensional barcode formats. Understanding the differences between these formats will help you choose the right one for your application.

CODE128: CODE128 is a high-density linear barcode symbology that can encode all 128 ASCII characters. It is widely regarded as the most versatile and efficient one-dimensional barcode format. CODE128 uses a switching mechanism that allows it to encode numeric data very compactly when the data consists primarily of digits. It is commonly used in shipping and packaging, supply chain management, and inventory control. If you are unsure which format to use, CODE128 is an excellent default choice because of its broad character support and compact encoding.

CODE39: CODE39 (also known as Code 3 of 9) is one of the oldest barcode formats, developed in 1974. It can encode uppercase letters A through Z, digits 0 through 9, and a handful of special characters including space, dash, period, dollar sign, slash, plus, and percent. CODE39 is widely used in the automotive industry (as specified by the Automotive Industry Action Group), the Department of Defense, and in healthcare for patient identification. While it does not support lowercase letters, its simplicity and wide scanner support make it a reliable choice for applications that only require alphanumeric data in uppercase.

EAN-13: The European Article Number (now officially called the International Article Number) is a 13-digit barcode standard used worldwide for identifying retail products. EAN-13 is the most common barcode format seen on consumer goods sold in stores. The first 7 to 9 digits represent a GS1 company prefix, the next 3 to 5 digits identify the specific product, and the final digit is a check digit calculated from the preceding digits to ensure accuracy. EAN-13 is compatible with and supersedes the older UPC-A format used primarily in North America.

EAN-8: EAN-8 is a shortened version of EAN-13, encoding exactly 8 digits. It is used when the physical space available for the barcode is too small to accommodate a full EAN-13 code, such as on small consumer products like chewing gum packs, cigarettes, or cosmetics. EAN-8 codes are assigned by GS1 member organizations and are generally reserved for products where a full EAN-13 cannot be printed.

UPC: The Universal Product Code (UPC-A) is a 12-digit barcode format primarily used in the United States and Canada for retail product identification. It is the standard barcode format required by most North American retailers for point-of-sale scanning. The structure is similar to EAN-13, consisting of a manufacturer identification number, a product code, and a check digit. Any EAN-13 scanner can also read UPC-A codes, making it compatible with global scanning systems.

ITF-14: ITF-14 (Interleaved 2 of 5, 14 digits) is a barcode format designed specifically for marking cartons, cases, and pallets in the supply chain. It encodes a 14-digit GTIN (Global Trade Item Number) and is printed directly on corrugated cardboard packaging. ITF-14 uses a robust encoding scheme that makes it highly reliable for scanning in warehouse and distribution environments where printing quality may vary. It is the standard format for the SSCC (Serial Shipping Container Code) used in logistics.

When to Use Each Type

Choosing the right barcode format depends on your specific use case and the requirements of the systems that will be scanning your barcodes. Here are some practical guidelines to help you decide:

• General-purpose encoding: Use CODE128 when you need to encode arbitrary text, URLs, serial numbers, or mixed alphanumeric data. It offers the best data density and widest character support.
• Retail products (global): Use EAN-13 for products that will be sold in retail stores outside North America, or when you need global compatibility. You must obtain a GS1 company prefix to create valid EAN-13 codes.
• Retail products (North America): Use UPC for products sold primarily in the United States and Canada. Most US and Canadian retailers require UPC codes for point-of-sale scanning.
• Small retail products: Use EAN-8 when the product packaging is too small for a full EAN-13 or UPC code. Note that EAN-8 prefixes must be obtained from your local GS1 organization.
• Shipping cartons and pallets: Use ITF-14 for marking outer packaging in supply chain logistics. ITF-14 is specifically designed for printing on corrugated cardboard.
• Industrial and defense: Use CODE39 when working with systems that require or expect CODE39 formatting, such as automotive industry applications or Department of Defense standards.

Frequently Asked Questions

Do I need a GS1 prefix to generate barcodes?

For EAN-13, EAN-8, UPC, and ITF-14 formats used in retail and supply chain applications, you generally need a GS1 company prefix to create valid codes that will be recognized by retailers and scanning systems. However, for internal use, asset tracking, or non-retail applications, you can generate CODE128 or CODE39 barcodes with any data you choose without a GS1 prefix.

What is the difference between EAN-13 and UPC?

EAN-13 is a 13-digit format used internationally, while UPC (UPC-A) is a 12-digit format used primarily in North America. EAN-13 was developed as a superset of UPC-A, and any UPC scanner can read EAN-13 codes (and vice versa, since EAN-13 scanners have always been backward-compatible with UPC-A). A UPC code can be converted to EAN-13 by prepending a zero digit.

Can I print barcodes on any printer?

Yes, barcodes generated by our tool can be printed on any standard printer. For best results, use a laser printer or a high-quality inkjet printer with sharp, black bars on a white background. The minimum print resolution should be 300 DPI for most barcode formats. Avoid printing barcodes on textured or glossy paper, as this can interfere with scanning reliability.

How do I verify that my barcode scans correctly?

After generating and printing a barcode, you should verify it with a barcode scanner or a barcode scanning app on your smartphone. Compare the scanned result with the original data to ensure accuracy. For professional use, consider using a barcode verifier, which provides detailed analysis of barcode quality including print contrast, quiet zone compliance, and decode accuracy.

What resolution should I use for barcode images?

For screen display, the default resolution from our generator is usually sufficient. For print applications, download the barcode image and ensure it is printed at a minimum of 300 DPI. The barcode should be sized so that the narrowest bar is at least 0.25 mm (10 mils) wide for most scanning environments. Larger bar widths provide better scanning reliability.