Code 39 Barcode Generator — Industrial & Defense Standard
Create classic Code 39 industrial barcodes with uppercase alphanumeric support and optional check digits.
Barcode Generator
Preview ↓Widely used industrial barcode supporting uppercase letters, digits, and select punctuation.
SVG is recommended for physical printing. PNG is ready for digital usage.
Generated entirely in your browser without network requests. Renders standard symbology geometry locally — creating a barcode image does not issue, register, or license a GS1 identifier.
How to Use
- Type your uppercase alphanumeric code, asset tag, or part number into the input field.
- If lowercase letters are entered, click the 'Uppercase' helper button to normalize automatically.
- Inspect the live SVG barcode preview for instant visual confirmation.
- Adjust sizing, bar height, margin, or colors under Appearance Settings if needed.
- Download SVG for laser/thermal label printing or PNG for digital documentation.
About This Format
Code 39 (often referred to as Code 3 of 9) is a discrete, variable-length linear barcode defined under ANSI/AIM BC1 and ISO/IEC 16388. It encodes 43 discrete characters: uppercase English letters (A–Z), numeric digits (0–9), and seven special characters (space, -, ., $, /, +, %). Each character pattern contains 9 elements (5 bars and 4 spaces), with exactly 3 wide elements. Code 39 is standard in industrial manufacturing, aerospace, and defense applications.
Validation & Technical Constraints
- Supported characters: A-Z (uppercase only), 0-9, space, and symbols: - . $ / + %.
- Standard Code 39 does not accept lowercase letters; use uppercase normalization.
- Start and stop delimiter asterisks (*) are automatically managed by the encoder.
Examples
Industrial Part Number
PART-1234-A
Military Standard Asset Tag
MIL-STD-884
Uppercase Inventory Code
CODE-39-SAMPLE
Frequently Asked Questions
Standard Code 39 only defines uppercase letters (A–Z). Lowercase characters trigger an encoding validation error. Our tool includes an automatic uppercase conversion button so you can quickly normalize input with a single click.
Each encoded character pattern comprises nine elements (bars and spaces combined), exactly three of which are wide while the remaining six are narrow.
No. In Code 39, the asterisk character serves as the start/stop delimiter. The encoder automatically generates these framing patterns into the symbol.
Choose Code 39 if your workflow or legacy industrial scanners explicitly require Code 3 of 9 compliance (such as DoD MIL-STD-129 labels). For new projects requiring compact size or lowercase characters, Code 128 is typically preferred.