The Complete Barcode Generator Guide
A barcode encodes data as a visual pattern of parallel bars and spaces, and it is used worldwide for product management, logistics, and inventory tracking. With this barcode generator you can create the major barcode symbologies — EAN-13, Code 128, and Code 39 — instantly in your web browser, with no software to install. Everything is generated locally on your device: your data never leaves your browser, so nothing is uploaded to a server. The finished barcode can be downloaded as a crisp PNG or scalable SVG file, ready to drop straight into labels, packaging, price tags, or print materials.
Supported barcode symbologies
EAN-13 is the most widely used retail product barcode in the world. Based on the European Article Number system, it takes 12 digits and automatically appends a single check digit for a total of 13 digits. The first digits identify the country or numbering authority that issued the code. EAN-13 is what point-of-sale (POS) systems scan at supermarkets and convenience stores to identify a product and look up its price.
Code 128 is a high-density barcode capable of encoding the full set of 128 ASCII characters. It handles digits, uppercase and lowercase letters, and special characters, which makes it ideal for shipping labels, medical device tags, electronics tracking, and many other industrial uses. It can pack the same data into roughly 30% less space than Code 39, making it a space-efficient choice for dense data.
Code 39 is one of the oldest barcode standards still in common use. It supports uppercase letters (A–Z), digits (0–9), and a handful of symbols (- . $ / + % and space). It has long been adopted as a standard in the automotive industry, by the U.S. Department of Defense, and in healthcare, and its simple structure allows reliable scanning even without a checksum.
Where barcodes are used
- Retail: price lookups, inventory management, POS integration
- Logistics & shipping: package tracking, automated sorting, inbound/outbound control
- Libraries & publishing: book management via ISBN barcodes
- Healthcare: patient wristbands, medication management, specimen tracking
- Manufacturing: process control, quality tracing, parts identification
- Events: ticketing, access control, coupon codes
Tips for generating reliable barcodes
When printing barcodes, a resolution of at least 300 dpi is recommended. Always leave enough clear space (the "quiet zone") around the barcode so scanners can read it accurately — EAN-13, for example, needs a margin of at least 3.63mm on each side. Contrast matters too: a black barcode on a white background gives the highest contrast and the most reliable scans. Avoid stretching or distorting the barcode, and test it with a real scanner before mass-producing labels.
Frequently asked questions (FAQ)
Q. Can I put letters into an EAN-13 barcode?
A. No. EAN-13 supports digits only and requires exactly 12 digits (the 13th check digit is calculated automatically). If you need to include letters, use the Code 128 or Code 39 format instead.
Q. Can I use the barcodes I generate commercially?
A. Yes, the barcode images produced by this tool are free to use. However, to sell a product carrying an EAN-13 barcode through retail channels, you must obtain an official company prefix from GS1, the global standards body that issues unique barcode numbers.
Q. What size should a barcode be?
A. The standard EAN-13 barcode at 100% magnification is about 37.29mm wide by 25.93mm tall. It can be reduced to roughly 80% (about 29.83mm wide) and enlarged up to 200%. Choose a size that suits your printing environment.
Q. What is the difference between Code 128 and Code 39?
A. Code 128 supports the full ASCII character set and has a higher data density, so it represents the same data in less space. Code 39 supports only uppercase letters and digits, but its simple structure and broad compatibility make it popular in legacy systems.