ITF-14 Barcode Guide: Specifications for Corrugated Master Shipping Cartons

Why You Cannot Print Standard EAN-13 Directly onto Brown Cardboard

In international supply chain logistics, individual consumer products carry an [EAN-13 Barcode](/ean-13-barcode) or [UPC-A Barcode](/barcode). However, when 24 or 48 of those individual items are packed into a heavy corrugated cardboard master carton for warehouse shipping, standard retail barcodes fail.

Direct flexographic printing onto porous, uneven kraft paper causes ink bleed (dot gain) along the corrugated flutes. Fine barcode bars expand and swallow narrow spaces, rendering high-density retail barcodes completely unscannable by automated warehouse cameras.

The global packaging industry solves this problem with the **ITF-14 Barcode**.

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1. Interleaved 2 of 5 (ITF) Mechanics

ITF-14 encodes 14 numeric digits using the **Interleaved 2 of 5** symbology:

• **Interleaved Encoding:** Digits are encoded in pairs. The first digit is represented by 5 dark bars, while the second digit is represented by the 5 intervening light spaces.
• In each group of 5 elements, exactly **two are wide and three are narrow** (hence "2 of 5").
• Because spaces carry active data rather than just separating bars, ITF achieves a robust, wide optical tolerance that resists ink absorption on rough cardboard surfaces.

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2. The Anatomy of an ITF-14 Number

An ITF-14 number is a 14-digit Global Trade Item Number (GTIN-14) composed of four distinct segments:

1. **Indicator Digit (1st digit):** Denotes the packaging level (e.g., `1` for a standard case carton, `2` for an inner pack, `0` or `9` for variable measure bulk).
2. **GS1 Company Prefix (Next 6–10 digits):** The manufacturer's globally registered GS1 business identifier.
3. **Item Reference (Next 2–6 digits):** Identifies the specific product contained within the master carton.
4. **Modulo-10 Check Digit (14th digit):** Calculated using the standard GS1 Modulo-10 checksum algorithm to guarantee barcode reading integrity.

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3. The Function of Bearer Bars

A signature visual element of every authentic ITF-14 barcode is the thick horizontal line border surrounding the bars, known as **Bearer Bars**:

• **Printing Plate Support:** During flexographic printing presses, heavy roller cylinders exert physical pressure onto cardboard. The bearer bars equalize mechanical pressure across the printing plate, preventing the plate from flexing and crushing the delicate barcode lines.
• **Preventing "Short Scans":** When a hand scanner passes across an angle through an unprotected linear code, it might read only a fraction of the digits. Bearer bars create an immediate quiet barrier that forces scanning beams to traverse the entire 14-digit sequence or reject the read entirely.

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4. GS1 Magnification & Nominal Dimensions

• **Nominal Size (100%):** Width is 142.75 mm (5.62 inches) and height is 31.75 mm (1.25 inches).
• **Allowed Range:** GS1 allows magnification scaling from **50% (0.50)** up to **100% (1.00)** for pre-printed labels, and from **80% (0.80)** up to **100% (1.00)** for direct carton flexo printing.
• Export high-precision vector SVG files from our [Barcode Studio](/barcode) to ensure bearer bars and space ratios conform strictly to GS1 ISO/IEC 16390 specifications.