Make it, print it, prove it scans
A barcode that won't scan costs a print run, a rejected delivery or a queue at the till. This checker catches the common causes before that happens. Make a barcode with our generator, press Test it scans, and the checker opens on your phone already set to that barcode.
Two ways to check
| Check | How | What it tests |
|---|---|---|
| A printout | Press Scan a printout and hold the camera over the printed barcode for 3 seconds | Reads, matches, check digit, contrast, and how often it reads (read rate) |
| An image file | Press Check an image file, or drop or paste it here | All of the above, plus sharp edges, even bar widths, blank margins and print size |
What each check means
- Reads: the barcode can be decoded at all.
- Matches: it says exactly what you typed under What should it say. A barcode that scans the wrong number is worse than one that doesn't scan.
- Check digit: for UPC, EAN, ISBN, GTIN and SSCC numbers, the last digit is correct.
- Contrast: dark bars on a light background. Red or yellow bars fail, because most scanners use red light and can't see them.
- Sharp bars: no blurred pixels at the bar edges, which appear when an image is resized.
- Even bar widths: every bar is a whole number of pixels, so the printer doesn't round some bars wider than others.
- Blank margins: enough empty space (the quiet zone) on each side, measured in bar widths. UPC-A needs 9, EAN-13 needs 11 on the left and 7 on the right, Code 128 needs 10.
- Print size: from the file's resolution. Retail barcodes should print at 80% to 200% of standard size; shipping labels need bars at least 0.495 mm wide.
What this isn't
Retailers and logistics companies sometimes ask for an ISO/IEC 15416 verification report. That needs a calibrated verifier measuring reflectance under controlled light, which a phone or an image file can't replace. This checker finds the problems that cause most failures, quickly and for free; if a customer demands a graded report, use a barcode verification service.
