Barcode Generator and Check Digit Validator
Make UPC, EAN, ITF-14, Code 128 and Code 39 barcodes in your browser. The tool calculates or checks the check digit, explains the GS1 prefix, sets the print size in millimeters, and downloads PNG or SVG. Need many? Paste a list or fill a sequence and download them all as a ZIP file.
Free · No sign-up
How to use it
- Choose the barcode type: EAN-13 or UPC-A for retail products, ITF-14 for cartons, Code 128 for text labels.
- Type the number. For EAN and UPC you can leave out the last digit and the check digit is added for you.
- If the check digit is wrong, use the corrected code or one of the suggested fixes.
- Set the size and colors if needed, then download the barcode as PNG or SVG.
- For many barcodes, paste a list or fill a sequence below and download a ZIP file or print them.
Why use this tool
Six barcode types
EAN-13, UPC-A, EAN-8 and ITF-14 for GS1 numbers, plus Code 128 and Code 39 for text and serial numbers.
Check digit validator
Adds a missing check digit, flags a wrong one with the correct value, and suggests the code you meant if two digits were swapped.
GS1 prefix lookup
Shows which GS1 office issued a number, and recognizes book (ISBN), magazine (ISSN) and in-store codes.
Real print sizes
Bar width in millimeters from 80% to 200%, a PNG that carries its print resolution, and an SVG measured in millimeters.
Bulk ZIP and printing
Up to 500 barcodes from a list or a numbered sequence, as PNG or SVG files in one ZIP, or printed on a sheet.
Private and free
Everything runs in your browser. No sign-up, no watermark, and your codes are not uploaded.
Which barcode type do you need?
The right type depends on where the barcode will be scanned. Retail checkouts read the EAN/UPC family, which carries a GS1 product number (GTIN). Warehouses and internal systems often use Code 128.
| Type | Content | Typical use |
|---|---|---|
| EAN-13 | 13 digits | Products sold in shops worldwide, books (ISBN) |
| UPC-A | 12 digits | Products sold in the USA and Canada |
| EAN-8 | 8 digits | Very small packages |
| ITF-14 | 14 digits | Cartons and outer cases in a warehouse |
| Code 128 | Letters, digits, symbols | Shipping labels, inventory, serial numbers |
| Code 39 | A–Z, 0–9 and a few symbols | Older industrial and internal systems |
How the check digit is calculated
EAN, UPC and ITF-14 numbers end with a check digit that lets a scanner catch a misread code. GS1 uses the same modulo 10 method for all of them. Here it is for the example on this page, 01234567890:
- Start at the rightmost digit and multiply the digits by 3 and 1 in turn: 3, 1, 3, 1 and so on.
- For 01234567890 the weights from left to right are 3 1 3 1 3 1 3 1 3 1 3, and the results are 0 1 6 3 12 5 18 7 24 9 0.
- Add the results: 85.
- Round up to the next multiple of 10 (90) and subtract the sum: 90 − 85 = 5.
- So the full UPC-A number is 012345678905. If the sum is already a multiple of 10, the check digit is 0.
What the first digits (GS1 prefix) mean
The first three digits of an EAN-13 show which GS1 office issued the company number. They do not say where the product was made, because companies can join GS1 in the country where they are based. A UPC-A number is read with a leading zero, so 036000291452 has the prefix 003. Some common prefixes:
| Prefix | Issued by or used for |
|---|---|
| 001–019, 030–039, 050–139 | GS1 US |
| 754–755 | GS1 Canada |
| 500–509 | GS1 UK |
| 930–939 | GS1 Australia |
| 890 | GS1 India |
| 020–029, 200–299 | Restricted circulation, defined by each GS1 office (for example in-store codes) |
| 977 | Magazines and other serials (ISSN) |
| 978–979 | Books (ISBN) |
Barcode size and print quality
An EAN-13 barcode is 95 bars wide (measured in narrow bars, or modules) plus clear margins: at least 11 modules on the left and 7 on the right. GS1 gives these bar widths and heights for products scanned at a checkout. The total width is calculated from those 113 modules:
| Size | Bar width | Bar height | Width with margins |
|---|---|---|---|
| 80% | 0.264 mm | 18.28 mm | 29.83 mm |
| 100% | 0.330 mm | 22.85 mm | 37.29 mm |
| 200% | 0.660 mm | 45.70 mm | 74.58 mm |
Colors that scan
Black bars on a white background are the best choice. Scanners use red light, so bars in red or reddish colors such as brown disappear for them, and light bars on a dark background cannot be read at all. Dark blue or dark green bars on white usually work. The tool warns you when your colors may not scan.
Frequently asked questions
Is this barcode generator free for commercial use?
Yes. There is no sign-up, no watermark and no limit on use, including on products you sell. The barcode image is yours. For retail products, the number itself must come from GS1, as explained below.
Can I make up my own UPC or EAN number?
Not for products sold in shops. Retail numbers must contain a company prefix licensed from GS1, otherwise two products could share a number. Numbers starting with 200 to 299 (or 020 to 029 for UPC) are for restricted circulation, such as codes used only inside your own store.
What happens if the check digit is wrong?
Scanners reject the code, so it cannot be sold through a checkout. The tool shows the correct check digit and offers the corrected code. If two neighboring digits were swapped, it also suggests the codes you probably meant.
What is the difference between UPC-A and EAN-13?
UPC-A has 12 digits and is used in the USA and Canada; EAN-13 has 13 digits and is used everywhere else. A UPC-A number is the same as an EAN-13 with a leading zero: 036000291452 and 0036000291452 are one product. Retail scanners generally read both.
Which barcode should I use for shipping cartons?
ITF-14 is the usual choice for cartons and outer cases that carry a GS1 number. GS1 asks for bars at least 0.495 mm wide and 31.75 mm high for it. For text such as order or tracking numbers, use Code 128.
Should I download PNG or SVG?
SVG is a vector file: it stays sharp at any size and is best for packaging design, print shops and label software. PNG is a picture file that works everywhere. The PNG from this page stores its print resolution, so it prints at the size you chose.
Does Amazon accept these barcodes?
Amazon checks UPC and EAN numbers against GS1 data in most categories, so the number must be licensed to your company by GS1. Numbers bought from resellers are often rejected. The barcode image from this page is fine; what matters is the number in it.
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