Create a barcode separator sheet

Which code should you use?

Code 128 is the standard for separator sheets. It is compact, read cleanly by practically every scanner, and handles letters and digits. For a plain separator sheet, a short, always-identical content such as SPLIT is enough.

QR code also works and has one advantage: it is still read even if the sheet is rotated or fed in slightly skewed. On batch scanners with automatic feed, that is a real argument. The downside is the larger space requirement.

Code 39 is older and less dense, but still common in existing archive workflows. If you already have templates with it, there is no reason not to keep using it.

More important than the type is that the code is cleanly recognisable on the finished scan. And that is decided at print time.

Laying out the sheet correctly

Size. The code should be at least about 3 cm wide. Smaller becomes unreliable at 200 dpi scan resolution.

Quiet zone. Clear white space must remain around the code — as a rule of thumb, about ten times the width of a narrow bar. This is the most common mistake: the code sits too close to the page edge or right next to text and becomes unreadable.

Contrast. Black on white. No grey, no colour, no screened background. If you print separator sheets on a laser printer with a toner-saving mode, switch that mode off for these pages.

Placement. Always in the same spot, ideally the top third. Some recognition engines look there first, and on a skewed sheet the code still stays within the expected area.

Paper. Plain printer paper is fine. If you reuse the same sheets, slightly heavier paper pays off, since worn edges eventually cause feed errors.

The workflow

1. Print separator sheets — as many as you need to split, plus a few spares.
2. Build the stack — place one separator sheet between every two documents.
3. Scan in one pass — one PDF, all documents, all separator sheets.
4. Open it in StackSplitter — choose barcode as the split method.
5. Download the result as a ZIP — one PDF per document, separator sheets removed.

When detection fails

If the tool fails to detect individual separator sheets, it is almost never the code itself but the scan:

• Resolution too low. Below 200 dpi it becomes unreliable. 300 dpi is safe.
• Compressed too aggressively. Some scanners compress so hard that bars merge together. Back off one setting.
• Fed in skewed. A slight skew is normal, a strong one makes narrow bars unreadable. QR instead of Code 128 helps here.
• Dirty feed rollers. Sounds mundane, but on high-volume scanners it is the most common cause of streaks across the code.