Free Code 128C Barcode Generator — Ultra-Compact Numeric Barcode Encoding

Generate Code 128C barcodes online for free. Code 128C encodes digit pairs (00–99) with maximum efficiency — producing the narrowest possible Code 128 barcode for numeric-only data. Ideal for GTINs, serial numbers, lot codes, and any long numeric string where label space is constrained. Download as PNG or SVG instantly. No signup, no watermarks, no limits.

What Is Code 128C?

Code 128C is the numeric-optimized subset of Code 128 that encodes pairs of digits — each two-digit sequence (00 through 99) maps to a single Code 128 symbol character. This halves the barcode width compared to Code 128B for the same numeric string, making Code 128C the most compact 1D barcode format available for pure numeric data. Standardized within ISO/IEC 15417, Code 128C requires an even number of digits as input — data must be padded to even length if necessary. It is widely used for GTINs, ITF-14 equivalents, lot numbers, serial numbers, and any high-density numeric label application.

Two Digits Per Symbol — Maximum Numeric Density
Code 128C encodes every pair of consecutive digits (00, 01, 02 … 99) as a single barcode symbol character. A 12-digit EAN-compatible number requires only 6 symbol characters in Code 128C, compared to 12 in Code 128B. This 50% reduction in barcode width allows Code 128C to fit long numeric strings on label stock where a full-width Code 128B barcode would not fit — without reducing the X-dimension or bar height.
Even-Length Digit-Only Input Required
Code 128C accepts only digit characters (0–9) and requires an even number of digits. If your numeric string has an odd number of digits, pad it with a leading zero to make the length even before encoding. Non-digit characters (letters, punctuation, spaces) are not valid in Code 128C. For mixed alphanumeric data, use Code 128B or Code 128 auto mode.
Ideal for GTIN, Lot Number, and Serial Number Labels
Code 128C is the preferred encoding for numeric GTINs (GTIN-12, GTIN-13, GTIN-14), serial numbers, lot codes, and batch identifiers that are long numeric strings. The compact output fits within narrow label widths on product tags, coupons, and logistics cartons where space is at a premium. GS1-128 (Application Identifier barcodes) frequently uses Code 128C for numeric application identifier data fields.
Automatic Mod 103 Check Character
Code 128C includes the standard Mod 103 check character computed and inserted automatically. The check character ensures reliable scanner decoding and rejection of corrupted barcodes, providing the same error detection reliability as Code 128A and Code 128B in a smaller physical footprint.

Code 128C Barcode Generator Features

Generate compact, high-density Code 128C barcodes for numeric data with real-time validation, size controls, and instant download.

Even-Digit Validation and Error Feedback

The generator validates Code 128C input in real time: non-digit characters and odd-length strings are flagged immediately with clear error messages before encoding. This prevents producing non-compliant barcodes that scanners would reject. The preview updates only when the input is a valid even-length digit string.

Narrower Barcode for the Same Data

Enter any even-length numeric string and compare the Code 128C output width against the same value encoded in Code 128B or Code 39. Code 128C produces a barcode that is approximately half the width of Code 128B for the same digit count — a critical advantage when printing numeric barcodes on small labels or in multiple-column label layouts.

PNG and SVG Download

Download your Code 128C barcode as a scalable SVG for print-ready output or as a high-resolution PNG for documents and label software. The compact Code 128C barcode scales clearly at any resolution in SVG format.

Bar Height and Width Control

Adjust bar height and X-dimension to meet the physical requirements of your label. Taller bars improve scan angle tolerance on handheld and fixed-mount scanners. Wider modules compensate for low-resolution thermal label printers. Quiet zones are calculated and included automatically at the ISO-required minimum.

Bulk Numeric Barcode Generation

Paste a column of even-length numeric strings — GTINs, serial numbers, lot codes — and generate all Code 128C barcodes in one operation. Download as a ZIP of PNG or SVG files for batch label printing or integration into a label management system.

Code 128C — Frequently Asked Questions

Technical answers about Code 128C encoding rules, length requirements, and comparison with other numeric barcode formats.

Why does Code 128C require an even number of digits?

Code 128C encodes two digits at a time as a single symbol character. The 100 possible two-digit pairs (00–99) each map to one of the 100 data symbol values in the Code 128 encoding table. Since every character position encodes exactly two digits, the total digit count must be even. If your number has an odd digit count, prepend a leading zero (for example, encode '12345' as '012345') to make it even-length.

Is Code 128C the same as ITF (Interleaved 2 of 5)?

No, but they serve a similar purpose. Both Code 128C and ITF encode pairs of digits with high density. Key differences: Code 128C includes a mandatory Mod 103 check character providing error detection; ITF uses a separate check digit algorithm and it is optional. Code 128C can be mixed with Code 128A/B within a single barcode using auto mode; ITF is a standalone symbology. Code 128C is more compact than ITF for the same number of digits and offers better scanner compatibility with modern imagers.

Can Code 128C encode letters or special characters?

No. Code 128C is strictly limited to even-length digit strings. It cannot encode letters, spaces, or any non-digit character. For alphanumeric data, use Code 128B. For mixed numeric and alphabetic data of varying length, use Code 128 auto mode, which will switch to Code 128C for long digit runs and Code 128B for alphabetic sections.

How much smaller is Code 128C compared to Code 128B?

For a given even-length numeric string, Code 128C produces a barcode approximately 50% narrower than Code 128B encoding the same digits. For example, a 12-digit string requires 6 symbol characters in Code 128C versus 12 in Code 128B. This means a Code 128C barcode for 12 digits is roughly half the physical width of the equivalent Code 128B barcode at the same X-dimension.

Generate Your Code 128C Barcode Now — Free, Instant, No Signup

Create compact, high-density Code 128C barcodes for numeric data right now. Enter your even-length digit string, adjust the size, and download as PNG or SVG — completely free with no account required.