Online Code 39 Generator
13 one- / two-dimensional barcode formats, check digits computed automatically.
What is Code 39?
Code 39 encodes A–Z, 0–9 and -. $/% (ISO/IEC 16390), with a * start/stop by default. It underpins US military standard C-478408 and remains the go-to symbology for aviation part numbers and military logistics.
Encoding rules and capacity
- Uppercase letters, digits and a few symbols only (lowercase must be converted);
- Inter-character gap makes aiming more forgiving than Code 128;
- Start/stop characters customizable (e.g. A/B style) or default asterisks;
- Check digit optional (mod 43).
How to generate a Code 39 barcode
- Type uppercase letters/digits, e.g.
AB-1234; - Pick your start/stop style;
- Adjust height, colors and margins;
- Download PNG/SVG or print directly.
Typical uses
- Aviation and defense part numbers;
- Vehicle and tool asset tags;
- Legacy compatibility — many production lines still require Code 39.
FAQ
Does the online Code 39 generator require an account or payment?
No. Every CodeBox tool is 100% free, no sign-up, unlimited use, and all processing happens locally in your browser.
Which characters does Code 39 support?
Digits and letters (see the spec section for this symbology); example: AB-1234.
Can I download a vector format?
Yes. PNG (512–2048 px) and SVG vector output are both supported; SVG is ideal for print and large formats.
Is my data uploaded anywhere?
No. CodeBox is a fully client-side tool — your data is processed only on your device and never touches a server.
Can I print the barcode?
Yes. The tool has built-in printing; for bulk runs use the batch QR generator to lay out A4 sheets.