How to use the barcode generator
- 1Choose the Barcode type.
- 2Type the Value. For EAN-13, UPC-A, EAN-8 and ITF-14, enter the digits without the check digit and it's added for you.
- 3Adjust Bar width and Height, and choose whether to show the number under the bars.
- 4Press SVG for print and design work, or PNG for documents and web pages.
EAN-13 check digit
EAN-13 · 400638133393
4006381333931 Weighted sum = 89; check digit = (10 − 89 mod 10) mod 10 = 1
Choosing a barcode type
| Type | Holds | Typical use |
|---|---|---|
| EAN-13 | 13 digits | Retail products worldwide |
| UPC-A | 12 digits | Retail products in the US and Canada |
| EAN-8 | 8 digits | Small packs with little label space |
| ITF-14 | 14 digits | Outer cartons and cases (GTIN-14) |
| Code 128 | Letters, digits, symbols | Shipping, inventory, asset tags, serial numbers |
| Code 39 | A–Z, 0–9 and a few symbols | Older industrial and ID systems |
For internal labels (stock locations, asset numbers), Code 128 is the usual choice: it's compact and holds any text you need. Retail products need EAN or UPC numbers from GS1.
EAN and UPC check digits
The last digit of every EAN, UPC and ITF-14 number is a check digit that lets scanners catch misreads. GS1's method:
- Starting from the rightmost data digit, multiply digits alternately by 3 and 1.
- Add the results.
- The check digit is the amount needed to reach the next multiple of 10: (10 − sum mod 10) mod 10.
For 400638133393 the weighted sum is 89, so the check digit is 1 and the full EAN-13 is 4006381333931. Enter a full number and the generator verifies the check digit instead, and tells you the correct one if it's wrong.
Do you need GS1-registered numbers?
For products sold through retailers or marketplaces, yes. EAN-13 and UPC-A numbers (GTINs) are only unique because GS1 member organizations issue company prefixes; a number you invent may belong to another company's product, and major retailers and marketplaces check GTINs against the GS1 registry.
You don't need GS1 numbers for barcodes used only inside your business: warehouse locations, asset tags, library or membership cards. Use Code 128 with your own numbering for those.
Print size and quiet zones
- EAN-13 is about 37.29 × 25.93 mm at 100% magnification; GS1 allows 80% to 200% for most retail packaging.
- Quiet zones: leave blank space on both sides of the bars: 11 modules on the left and 7 on the right of an EAN-13, 9 on each side of a UPC-A, and at least 10 times the narrowest bar for Code 128 and ITF-14.
- Bar height: don't shorten (truncate) retail barcodes; it makes them harder to scan in any direction.
- Colors: black bars on a white background scan best. Red bars don't work, because many scanners use red light.
Download the SVG for print so bar widths stay exact, and test a printed sample with a scanner.
Is anything I enter stored?
This tool runs entirely in your browser. Your text is not uploaded to our servers.