Code 128 Barcode Generator

What a Code 128 barcode holds

Code 128 is a linear barcode: the information sits in the widths of its vertical bars and the spaces between them, read along one line. It can encode the full printable ASCII set, so uppercase and lowercase letters, digits and punctuation can all appear in the same value. Warehouses, shippers and manufacturers use it because one symbol can carry an order number, a serial or a location code without changing format.

This generator accepts up to 80 printable characters, spaces included. Anything outside the printable range, such as a line break or an accented letter, is refused with a message instead of being guessed at. The generator draws plain Code 128, so it does not build GS1-128 messages with application identifiers. If your system needs one, type the final string exactly as it should be read.

The data lives inside the drawing. Once the file is printed, the symbol cannot be changed and it cannot count scans, so a label is only as current as the text that was encoded when it was made. For internal tags whose content is fixed at printing time, that is exactly the behavior you want.

Once a symbol is printed, its value is fixed. When the data changes, such as a new order number or a revised location, generate a new file rather than trying to alter the printed label. Keep a dated record of which value went on which label, so a replacement can be traced back to the original.

How to make a Code 128 barcode in three steps

1. 01

   Choose the type and enter the value

   Pick Code 128 in the Type list, or press Use an example to load a sample value. Type your text in the Value field. The hint under it lists the rule, printable ASCII up to 80 characters, and the preview updates as you type.

2. 02

   Set the colors and the bar dimensions

   Bar color and Background set the two colors. Keep the bars dark on a light background so scanners see strong contrast. Size changes the width of each narrow bar and Bar height sets how tall the bars are. Turn off Show the number if your label already prints the text elsewhere.

3. 03

   Check the preview, then download

   Look at the preview at the size it will print, and scan it with a handheld reader or a phone camera before you print a full run. Download SVG for print at any size, or PNG, JPG or WEBP for a screen or a document.

Where Code 128 barcodes are used

• Shipping and warehouse labels

  A carton label often needs an order or tracking number that is read at several points in the building. Code 128 holds that alphanumeric string in a compact symbol that fits a standard label.

• Stock and bin locations

  Shelf and bin codes such as A-12-03 mix letters, digits and hyphens. Printing every location in Code 128 means one format covers the whole store.

• Asset and equipment tags

  Tools and office equipment can carry an asset number that staff scan at a desk or inside a cabinet. Keep the number short, because each extra character makes the symbol wider.

• Sample and batch tracking

  Sample tubes and batch records need one unique value per container. Code 128 keeps mixed case, so a batch name with capitals and small letters can be encoded exactly as written.

• Job tickets and routing

  A production order printed as a barcode lets a scanner open the right job without retyping it. Print the same value as text on the ticket so people can read it when the scanner is down.

Tips for Code 128 labels that scan first time

Keep the value short

The 80 character limit is a ceiling, not a target. Shorter values produce narrower bars, which print more sharply and remain readable on a small label.

Mind the lowercase letters

Code 128 keeps lowercase letters, unlike Code 39. A value typed as ab-07 is encoded as ab-07, so your system must use the same case when it looks the value up.

Leave a margin on the label

The downloaded file includes a small blank margin around the bars, but a printed label needs its own clear space on every side. Keep text, lines and borders out of that area so the scanner can find the edges.

Print a test before a full run

Printer settings change the width of the bars. Print one label on the real printer and paper, scan it, and only then print the batch. If scans fail, try a larger Size before you change the value.

Code 128 questions