Free Barcode Generator
Generate standard Code 39 barcodes. Adjust line scaling, dimensions, and styling. Completely offline client-side code execution.
Barcode Settings
What is Code 39 Barcode Format?
Industrial Standard Symbol
Code 39 (also known as Code 3 of 9) is a variable-length, discrete barcode symbology widely used in inventory control, automotive logistics, and governmental administrative forms. It can encode 43 unique characters including capital letters, numbers, and key symbols. The name stems from its structure where 3 out of every 9 lines representing a character are wide.
Self-Checking Symbology
Unlike barcode systems like EAN/UPC which require strict mathematical parity checks to scan, Code 39 is self-checking. Any single character reading error will result in an invalid sequence rather than misreading one character for another, making it highly robust for standard physical laser scanner registers.
Frequently Asked Questions
Why does the barcode container have asterisk symbols?
In Code 39, the asterisk character `*` is reserved exclusively as the start and stop delimiter. Scanners look for the start `*` to determine scan direction and the end `*` to stop recording.
Can I use lowercase letters?
Standard Code 39 does not support lowercase letters. Our generator automatically converts lowercase characters to uppercase to preserve scan compliance.
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