Make a test label sized exactly for your printer. Bars are snapped to whole printer dots, EAN/UPC check digits are checked, and a solid bar and 1–4 dot lines show dead print-head dots and darkness problems. Then scan each code with your phone.
In the print dialog pick your label printer, set the paper size to the same label size, Scale 100% / Actual size, margins None, headers and footers off. To save a PDF choose "Save as PDF".
Preview of the exact sheet that prints. Only this sheet prints — the rest of the page is hidden.
4 × 6 in and 100 × 150 mm shipping labels (Amazon, Flipkart, Shopify, eBay, USPS, UPS, FedEx, Delhivery), 4 × 3, 3 × 2, 2.25 × 1.25 and 2 × 1 in product labels, 50 × 25, 50 × 30 and 40 × 30 mm barcode labels, 62 × 29 mm Brother DK, 58 mm and 80 mm thermal receipt rolls, or any custom size. You can print one label at the label's own page size, or fill an A4 or Letter sheet to test a laser or inkjet printer.
| What you see | Likely cause | What to do |
|---|---|---|
| White vertical line through the solid bar and every barcode | Dead or dirty print-head element | Clean the head with isopropyl alcohol; if the line stays, the print head needs replacing. Rotate barcodes so the line doesn't cut every bar |
| Print is gray or faint, 1-dot lines missing | Darkness too low, speed too high, wrong media | Raise darkness/heat in the driver, lower print speed, use direct-thermal labels |
| Bars run together, 1–2 dot gaps fill in | Darkness too high | Lower darkness a step at a time until the 1-dot lines are thin but solid |
| Barcode doesn't scan but looks fine | Bars too narrow for the scanner, quiet zone cut off, label scaled | Use a larger label or shorter data; keep 100% scale; check the X-dimension shown above |
| Frame missing on one side, print shifted | Label size or calibration wrong | Set the exact label size in the driver and run media calibration |
| Prints on every second label or across the gap | Gap/black-mark sensor not calibrated | Run auto-calibration; check the label type setting (gap, black mark, continuous) |
| Ruler shorter than real size | "Fit to page" or wrong DPI setting | Set scale 100% and the printer's real resolution |
This page makes test labels. For your own product, shipping or inventory labels use the Barcode & Label Generator, and for QR codes the QR Code Generator. For office printers, see the printer test pages.
Open-source credits: JsBarcode 3.12.3 (MIT) · qrcode-generator 2.0.4 by Kazuhiko Arase (MIT). QR Code is a registered trademark of DENSO WAVE INCORPORATED.
Pick your label size and printer resolution above, press Print test label, set the same paper size and 100% scale in the print dialog, then check the frame, ruler, solid bar and barcodes, and scan each barcode with a phone or your scanner.
Usually the bars are too thin for the printer (narrow bar smaller than 2 dots), the print is too light, the quiet zone was cropped, or the label was scaled. This tool snaps every bar to whole printer dots and keeps the quiet zones, and tells you the bar width it used.
It is the width of the narrowest bar. On a 203 dpi printer one dot is 0.125 mm, so 2 dots = 0.25 mm and 3 dots = 0.375 mm. Retail EAN/UPC codes should be at least 0.264 mm; Code 128 shipping labels commonly use 0.25–0.5 mm.
The last digit is calculated from the others with a weighted sum (3,1,3,1…). Type 12 digits for EAN-13 or 11 for UPC-A and the tool adds the right check digit. Type the full number and it tells you whether the check digit is correct and what it should be.
All four sides of the frame should print (none cut off), the ruler should measure correctly, the solid bar should be fully black with no white vertical lines (a white line is a dead print-head dot), the 1–4 dot lines should all be visible, and every barcode should scan on the first try.
The printer needs to re-learn the gap between labels. Run media calibration (on Zebra hold Feed until it flashes twice; on Rollo, TSC and others see the manual's auto-calibrate step), and make sure the label size in the driver matches the real labels.
Yes, with any printer that has a normal print driver: Zebra, Rollo, TSC, Xprinter, Munbyn, Brother QL, Dymo and 58 mm or 80 mm ESC/POS receipt printers set up as Windows or Mac printers. It also prints label sheets on laser and inkjet printers.
Yes. Patterns are generated with the open-source JsBarcode (MIT) and qrcode-generator (MIT) libraries, hosted on ITCOH Tools, and drawn as vector graphics. Test codes like 5901234123457 are standard example numbers and are not linked to any product.