Free Code 39 barcode generator
Code 39 is one of the oldest barcodes still in daily use. It is wider than Code 128, but it needs no checksum and is read by practically every scanner ever made.
Barcode format
Capital letters A-Z, digits 0-9, space and - . $ / + % only. Lower-case is converted to capitals.
Keep strong contrast (dark bars on a light background) and leave a clear margin, or scanners may fail to read it.
Preview
Rendering…
Everything is generated in your browser. Nothing is uploaded.
What is Code 39?
Code 39 encodes 43 characters: capital letters A to Z, digits 0 to 9, space and the symbols - . $ / + %. Each character is drawn as nine elements, three of them wide, hence the name.
The symbol is framed by an asterisk start and stop character. Your scanner strips these, and the generator adds them for you, so do not type an asterisk into your value.
When to use Code 39
Uppercase asset and equipment labels, for example LAPTOP-0417.
ID badges and membership cards read by older handheld scanners.
Automotive and defence-style part labelling where Code 39 is already specified.
How to make a Code 39 barcode
- 1
Enter capitals, digits, space or - . $ / + %. Lower-case letters are converted to capitals for you, and anything else is rejected.
- 2
Keep the value to 40 characters or fewer; Code 39 grows quickly.
- 3
Pick a bar height tall enough for hand scanning, then download SVG, PNG or PDF.
- 4
Test a printed label with the scanner that will actually read it.
Code 39 questions
Why does Code 39 turn my lowercase text into capitals?
The standard character set has no lower-case letters. The generator upper-cases your input and tells you it did so, so the barcode and your records match.
Is Code 39 or Code 128 better?
Code 128 is shorter for the same data and supports lower case. Code 39 is the safer pick when an existing system or scanner specifies it, or when print quality is poor, because its wide bars are forgiving.
Can I encode an asterisk?
No. The asterisk is reserved as the start and stop marker, so it cannot be part of the data in this generator.
Does Code 39 have a check digit?
An optional modulo-43 check exists, but most systems skip it and this generator does not add one. If your receiving system requires it, add the check character yourself to the value.
Related barcode formats
Need a code people scan with their phone?
Barcodes hold short numbers. For links, Wi-Fi, contact cards and more, create a QR code.
- No watermark
- No account for static codes