Barcode Generator

What this tool does

A barcode is a number or code written as bars that a scanner can read in a fraction of a second. This tool turns your value into a barcode, checks that the value is valid for the barcode type you choose, and places it on a label: a plain barcode, a product label with a price, a shelf edge label, an asset tag, a shipping label, a ticket and more. You can download one label as PNG, SVG or PDF, or print a full A4 sheet of sticker labels.

Everything is created in your browser. Product names, prices and numbers you type are not sent anywhere. Your last settings are remembered on this device, so the next batch of labels starts where you left off.

Barcode types at a glance

Different industries settled on different barcode types. The right one depends on what you are labelling and who will scan it.

Choosing the right type

If the barcode is for your own use, such as stock in a shop, files in an office or equipment in a school, use Code 128. It accepts letters and numbers, it is compact, and every modern scanner reads it. A code like ITM-0042 or a location like A-03-02 works well.

If the product will be sold in other shops or supermarkets, the shop's billing system will expect EAN-13 (or UPC-A in North America). That number cannot be made up; see the next section. For cartons that hold several retail units, ITF-14 is the standard. Codabar, MSI and Pharmacode are mainly needed when an existing system already uses them, for example a library catalogue or a packaging machine.

EAN, UPC and GS1 numbers

EAN-13 and UPC-A numbers identify a product worldwide, so they are issued by GS1, a non-profit organization with offices in most countries. For example, in the United States the licensing body is GS1 US and in the United Kingdom it is GS1 UK. A business joins as a member, receives a company prefix and then numbers its own products from that range. Fees depend on the number of products and the size of the business, so check the current rates directly with GS1.

This tool will draw a valid barcode for any EAN-13 number, but a valid check digit does not make a number yours. Supermarkets and online marketplaces increasingly check numbers against the GS1 database, and a product with a borrowed or invented number can be refused or confused with another product.

• Do not copy a number from another product, and do not buy cheap resold numbers without checking that the marketplace you sell on accepts them.
• The example numbers in this tool start with 2, a range GS1 reserves for in-store use such as items weighed at the counter. Use them only for testing or inside your own shop, never on packaging that will be sold elsewhere.
• Books use ISBNs, which are EAN-13 numbers starting with 978 or 979. ISBNs are issued by the national ISBN agency of each country. Type the ISBN with or without hyphens and the Book template prints it above the bars.

Check digits, with a worked example

EAN, UPC and ITF-14 numbers end in a check digit calculated from the other digits. If a scanner misreads one bar, the check digit no longer matches and the scan is rejected instead of charging for the wrong product. Enter the number without its last digit and the tool adds it. Enter all the digits and the tool confirms the check digit or shows the correct one.

Here is the calculation for the EAN-13 number 590123412345, which has 12 digits:

1. Starting from the right, multiply the digits alternately by 3 and 1: 5 x 3, 4 x 1, 3 x 3, 2 x 1, 1 x 3, 4 x 1, 3 x 3, 2 x 1, 1 x 3, 0 x 1, 9 x 3, 5 x 1.
2. Add the results: 15 + 4 + 9 + 2 + 3 + 4 + 9 + 2 + 3 + 0 + 27 + 5 = 83.
3. Find how much is needed to reach the next multiple of 10: 90 - 83 = 7.
4. The check digit is 7, so the full number is 5901234123457.

The same method works for EAN-8, UPC-A and ITF-14. A 10-digit ISBN uses a different check, so the tool converts it to the 13-digit form for you.

Printing labels that scan

Most scanning problems come from printing, not from the barcode itself. A few rules cover almost every case:

• Size: EAN-13 at 100% is about 37 x 26 mm including the blank margins, with the narrowest bar 0.33 mm wide. It can be reduced to 80% (about 30 mm wide). Below that, many shop scanners struggle. The status line under the preview shows the current percentage.
• Bar width: for Code 128 and other internal codes, keep the narrowest bar at 0.25 mm or more for an office laser or inkjet printer, and never below 0.19 mm.
• Quiet zone: the blank space on both sides of the bars is part of the barcode. Do not let text, borders or the edge of the sticker run into it. The tool always keeps the minimum for the type you choose.
• Contrast: print black or very dark bars on a white or light background. Scanners use red light, so red, orange or pink bars look like blank space to them, and light bars on a dark background often fail.
• Height: taller bars are easier to scan by hand. Aim for at least 8 to 10 mm.

For A4 sticker sheets on an office printer, choose the layout that matches your sheet in Export, print one test page on plain paper, and hold it against the sticker sheet in front of a light. If everything sits a millimetre or two off, use Printer alignment to move the whole page. Always print at Actual size or 100%, never Fit to page.

For thermal label printers (common in shops, warehouses and courier counters), set the label size in Design to match your roll, for example 50 x 25 mm or 100 x 150 mm, and download the one-label PDF. Each page is exactly one label, so the printer driver does not need to scale anything.

Making many labels at once

Choose List under Labels to make and paste values one per line, for example a column copied from Excel or Google Sheets. Choose Sequence to number items automatically: a start number, how many labels, the step, zero padding and an optional prefix and suffix. Start 1, 4 digits and prefix INV- gives INV-0001, INV-0002 and so on.

Sequences are useful for asset tags, files, rack locations and stock counts. For EAN-13 or ITF-14 sequences, enter the numbers without the check digit and each one gets its own check digit. Any value that is not valid for the chosen type is listed with the reason and left out of the export.

Batch labels can be downloaded as A4 sheets (the values fill the sheet in order and continue onto new pages), as a multi-page PDF with one label per page for a thermal printer, or as a ZIP file with one PNG per value.

Common mistakes to avoid

• Printing a sheet with Fit to page turned on, which shrinks every label so they no longer line up with the stickers.
• Stretching a barcode image in Word or a design program. Change the label size here instead, so the bars stay in proportion.
• Saving the PNG as JPG. JPG blurs the edges of the bars; keep PNG, SVG or PDF.
• Typing a letter O instead of the digit 0, or adding spaces inside a product code. What you type is exactly what the scanner returns.
• Using an invented EAN-13 on products for other shops, or reusing one number for two different products or sizes.
• Not testing. Scan a printed label with the scanner that will actually be used, or with a free barcode scanner app on a phone, before printing hundreds.