When the Barcode Generator seems to misbehave, the cause is usually one of two things: something stopped the tool from running, or it ran but the result is not usable. This guide starts with the fastest checks, then walks through the common problems and exact fixes.
Quick Checks First
- Refresh the page - a stalled session is the most common cause of nothing happening.
- Confirm the input is not empty and actually contains what you meant to submit.
- Try the smallest possible input; if that works, the issue is size, not the tool.
- Turn off browser extensions that block scripts, then reload and test again.
- Update or switch browsers if the problem repeats across sessions.
Common Problems and How to Fix Them
The scanner rejects my barcode.
Match the symbology to the reader - retail checkout expects EAN-13 or UPC, while Code 128 suits internal labels.
The check digit is wrong.
EAN-13 needs a valid final digit - recompute it from the first twelve numbers before generating the bars.
The bars look too thin to print.
Print at a sufficient width and resolution - narrow bars vanish in low quality output and scanners cannot resolve them.
The scanned number does not match mine.
You likely mixed symbologies - encode the value with the type your scanner is configured to read.
The symbol is wider than my label.
Shorten the value or reduce bar height - both keep the code inside a smaller footprint.
The digits under the bars are unreadable.
Scale the image up rather than stretching a tiny one - crisp digits depend on clean edges.
When It Works but the Output Is Poor
If the tool runs fine but the result misses, the problem is almost always the brief, not the software:
- Picking a symbology the scanner does not expect
- Ignoring the EAN-13 check digit rule
- Printing the bars too narrow to resolve
- Stretching a small image until the bars blur
How to Stop It Happening Next Time
- Keep a saved prompt template for every task you repeat.
- Change one setting per generation so causes stay obvious.
- Run a two-minute sanity test with known input after any update.
- Note every failure and its fix; a short troubleshooting log pays for itself.
Still Stuck?
Reproduce the problem with the smallest possible input and note the exact steps that triggered it. A one-line description of what you did, what you expected and what happened is enough to get a precise answer from support or a colleague.
Frequently Asked Questions
Which barcode type should I use?
Use EAN-13 for retail products and Code 128 for shipping, mail and internal labels.
Do I need to calculate a check digit?
EAN-13 requires one - include a valid final digit so scanners verify the number correctly.
Can it handle letters as well as numbers?
Yes - Code 128 accepts alphanumeric values, while EAN-13 is numeric only.
Is my barcode stored?
No - generation runs in your browser with nothing saved.
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