Free Online Barcode Generator
ToolPlexa’s barcode generator creates common one-dimensional barcode formats in the browser. Choose CODE 128, EAN-13, UPC-A, CODE 39, or ITF-14, enter a value, and download an SVG or PNG result. The tool is useful for prototypes, internal labels, inventory tests, classroom examples, and production artwork that will be reviewed by the responsible system before use.
A barcode image and a barcode identifier are not the same thing. This tool renders the data you provide; it does not assign a new GTIN, register a product, or make an arbitrary number acceptable to a retailer. For commercial supply chains, obtain identifiers through the appropriate organization and follow the exact print and quiet-zone requirements of the scanner or trading partner.
Choose the Right Barcode Format
CODE 128
CODE 128 is a compact, general-purpose linear format that can represent printable ASCII characters. It is common in logistics, internal asset labels, shipping workflows, and systems that need letters and numbers. Use it when the receiving software specifically supports CODE 128 and when you control the value format.
EAN-13
EAN-13 is used widely for retail item identification outside North America and is related to the GTIN family. The tool accepts the first twelve digits and calculates the check digit, or accepts all thirteen digits and verifies the final digit. A correct check digit is necessary but does not by itself register the product with a retailer.
UPC-A
UPC-A is a twelve-digit retail format commonly associated with North American point-of-sale systems. The tool can calculate or verify the final check digit. Confirm the number with your product-data provider before you print packaging or send artwork to a retailer.
CODE 39
CODE 39 is a straightforward alphanumeric format often used for internal labels. It supports uppercase letters, numbers, spaces, and a limited set of punctuation. It usually needs more physical width than a denser format for the same information, so size the label accordingly.
ITF-14
ITF-14 is used in many shipping and carton environments. It is not a replacement for an item-level retail code. Carton markings frequently have special bearer-bar, magnification, placement, and verification rules, so confirm the specification with the trading partner before production.
How to Generate a Barcode
1. Confirm the value first
Use an identifier that your organization is authorized to use. Check leading zeros, digit count, capitalization, and any required prefix. Never copy a barcode from an unrelated product and change one digit casually; the receiving database may treat it as a real but incorrect item.
2. Select the format used by the reader
Ask the inventory, point-of-sale, warehouse, or software owner which symbology is accepted. A visually sharp CODE 128 image will still fail if the scanner expects EAN-13. For retail use, follow the standard supplied by the retailer or product-identification authority.
3. Generate and validate
The generator checks common retail check digits when the format uses them and produces a visible value below the bars. Compare the displayed value with your source. Then scan the output using the Barcode Scanner or the receiving system’s own test scanner.
4. Download the production asset
Choose SVG for labels, packaging, and print artwork so the bars remain crisp during resizing. Choose PNG for a digital document only when its resolution is high enough for the final size. Do not stretch a barcode in one direction or apply blur, sharpening, or heavy compression after export.
Print Quality and Quiet Zones
A linear barcode needs clear space on both sides of the bars. This quiet zone helps the reader find the symbol and estimate where it starts and ends. Do not place text, borders, folds, stickers, or graphics too close to the bars. Keep strong contrast between bars and background; black bars on white are the safest starting point.
Print a proof at the smallest intended size and scan it under realistic lighting. Check curved packaging, glossy film, low-contrast material, label wrinkles, and the distance from a handheld scanner. A barcode that scans from a large monitor may fail when printed tiny on a carton. Professional production may require a verifier that measures symbol quality rather than relying only on a phone camera.
Standards and Product Identifiers
GS1 publishes specifications for GTINs, EAN, UPC, ITF-14, and related supply-chain identifiers. Review the GS1 barcode standards information and the requirements of your retailer or logistics partner. Country-looking prefixes are not a simple guarantee of where a product was manufactured, and a check digit is not a certificate of ownership.
For internal assets, define your own value convention and keep it documented. For a product sold through a marketplace, use the identifier assigned to that product rather than generating a convenient number from a random sequence. Retain the source data and version of the artwork so a replacement can be made without guessing.
Common Barcode Errors
- Using the wrong symbology for the receiving scanner.
- Removing leading zeros from a retail identifier.
- Changing a check digit instead of correcting the source number.
- Cropping the quiet zones or shrinking bars until they merge.
- Printing on a reflective, wrinkled, or low-contrast surface.
- Assuming a phone scan proves a retail verifier will pass it.
When the data is right but a test fails, isolate the problem: test the original SVG, a clean PNG, and the physical print; test another scanner; then compare the format and value expected by the system. This method is more reliable than repeatedly changing colors or adding decorative graphics.
Privacy and Operational Use
Barcodes often contain internal product, asset, or shipment references. The bars are not secret; anyone with a compatible reader may decode them. Avoid embedding credentials or sensitive personal data. If a label is public, assume its value can be copied. For ToolPlexa site-level information, see the Privacy Policy.
Frequently Asked Questions
Can I generate a barcode for a product I invented?
You can render a test value, but a production retail number must be assigned through the applicable identification process. Rendering a number does not reserve it or make it unique.
Why does my barcode look different from another generator?
Different libraries may choose different widths, fonts, margins, or text placement while encoding the same value. Compare the decoded value and the receiving specification, not only the visual appearance.
What if I need a two-dimensional code?
Use the QR Code Generator for URLs and text, or a specialized QR form for Wi-Fi, contact, and WhatsApp payloads.
Next Step
Create one proof, download it, scan it, and then test it in the system that will actually consume it. If you need a specific EAN-13 workflow, open the EAN-13 Barcode Generator. For the full collection, return to the QR and Barcode Tools category.