ITF-14 Case Code Checker
Case codes get rejected at goods-in far more often for their print specification than for a wrong number. Enter what you are about to print and this works out the finished size — quiet zones and bearer bars included — and which GS1 rules the spec breaks. It does not draw the barcode; it tells you whether the one you are drawing will pass.
🔒 Your data never leaves your browser.
Why the generators cannot tell you this
Every free ITF-14 generator draws the symbol and puts a bearer bar around it. None of them knows your press, your substrate or your carton. But the specification that decides whether the code scans at a distribution centre is written in terms of exactly those things:
- The bearer bar rule depends on how you print. On a press that uses printing plates the bearer bar is a constant 4.83 mm and has to surround the symbol completely, quiet zones included — it exists to equalise plate pressure. On a plateless process it only needs to be twice the narrow bar and only top and bottom. Judging one by the other’s number is how a perfectly good label gets called non-conforming.
- The minimum bar height does not shrink with the symbol. It is 31.75 mm at every X-dimension in the range, measured without the human readable digits or the bearer bars.
- Fine symbols must not be printed straight onto corrugate. Below 0.635 mm a conventional plate-based process should not print an ITF-14 directly on corrugate — the board cannot hold the detail. Put it on a label instead.
- Quiet zones are part of the symbol. Each side needs 10 × the X-dimension, and that space is measured as part of what you have to fit on the carton — which is why the size readout above includes it.
The size is computed, not estimated
The width comes from the formula in the General Specifications, W = (P(4N+6)+N+6)X + 2Q, where P is the number of character pairs (seven for an ITF-14), N the wide-to-narrow ratio, X the narrow element and Q one quiet zone. The specification’s own worked example — seven pairs at a 2.5:1 ratio, X of 1.016 mm and 10.16 mm quiet zones — comes to 142.75 mm, and that example is one of this tool’s regression tests.
What this tool does not do
It does not grade print quality. The 1.5/10/660 in the specification is an ISO/IEC 15416 grade measured with a barcode verifier at a stated aperture and wavelength; no browser can measure reflectance from a number you typed. It also does not judge artwork or photographs — the input is the specification you intend to print. And where the standard says a bearer bar may be omitted when it is “not technically feasible”, that feasibility is your call, not ours: the tool flags the omission rather than excusing it.
Every check this tool runs (13 rules)
ITF-001 GTIN-14 check digit is wrong
An ITF-14 encodes a GTIN-14, whose fourteenth digit is a mod-10 check digit over the preceding thirteen. A wrong check digit makes the symbol scan to a number that identifies nothing.
Fix: Recompute the check digit from the first thirteen digits.
ITF-002 X-dimension below the minimum
Symbol specification table 2 sets the smallest narrow element for an ITF-14 scanned in general distribution at 0.495 mm (0.0195 in). Below that the symbol is out of specification whatever else is right.
Fix: Raise the X-dimension to at least 0.495 mm, or print the case code on a label rather than the carton.
ITF-003 X-dimension above the maximum
The same table caps the ITF-14 narrow element at 1.016 mm (0.0400 in). Oversized symbols stop fitting the scanner’s depth of field in fixed-mount distribution scanning.
Fix: Reduce the X-dimension to 1.016 mm or below.
ITF-004 Bar height below the minimum
The minimum symbol height is 31.75 mm (1.250 in) at every X-dimension in the range — it does not shrink when the symbol is narrow. The height is measured excluding the human readable characters and the bearer bars.
Fix: Increase the bar height to at least 31.75 mm.
ITF-005 Quiet zone narrower than 10X
Quiet zones on both sides are compulsory and each must be at least ten times the X-dimension. With bearer bars the quiet zone is still measured as part of the symbol, so a bearer bar drawn tight against the bars eats it.
Fix: Widen each quiet zone to at least 10 × the X-dimension.
ITF-006 Wide-to-narrow ratio outside 2.25:1 – 3.0:1
ITF-14 allows a wide-to-narrow ratio between 2.25:1 and 3.0:1, with 2.5:1 as the target. Outside that band the reference decode algorithm stops separating wide from narrow reliably.
Fix: Set the ratio within 2.25:1 to 3.0:1 — use the 2.5:1 target unless the press requires otherwise.
ITF-007 Bearer bar missing
The bearer bar is mandatory unless it is not technically feasible to apply it. It equalises printing-plate pressure and stops short scans when a skewed beam leaves through the top or bottom edge.
Fix: Add a bearer bar sized for the print method, or record why applying one is not technically feasible.
ITF-008 Bearer bar thickness wrong for a plate-based press
For printing methods requiring plates the bearer bar has a constant thickness of 4.83 mm (0.190 in) and must completely surround the symbol including its quiet zones.
Fix: Set the bearer bar to 4.83 mm and make it enclose the symbol on all four sides.
ITF-009 Bearer bar thinner than twice the narrow bar
For printing methods that do not require plates the bearer bar must be at least twice the width of a narrow bar, appearing at least at the top and bottom.
Fix: Set the bearer bar to at least 2 × the X-dimension.
ITF-010 Plate-based press only needs top and bottom bearer bars where feasible
A plate-based press is specified to have the bearer bar completely surround the symbol. Where the bearer bar only runs top and bottom on such a press, the printing-pressure equalisation it exists for is only partly achieved.
Fix: Extend the bearer bar around all four sides, quiet zones included.
ITF-011 Too small to print directly on corrugate with a plate-based process
ITF-14 symbols with an X-dimension below 0.635 mm (0.0250 in) should not be printed directly on corrugate with conventional plate-based processes — the substrate cannot hold that detail. This is a "should not", so it is a warning rather than a hard failure.
Fix: Either raise the X-dimension to 0.635 mm or above, or print onto a label applied to the carton.
ITF-012 Gap between bearer bar and human readable characters too small
A minimum space of 1.02 mm (0.040 in) is required between the bottom line of the bearer bar and the top of the human readable characters.
Fix: Leave at least 1.02 mm between the bearer bar and the digits below it.
ITF-013 X-dimension is above the target
The target X-dimension for ITF-14 is 0.495 mm — the same as the minimum. Anything larger is inside the allowed range but makes the symbol physically wider, which is what usually stops a case code fitting the carton face.
About these rules. Each one has an identifier, a severity and a plain-English explanation. Every source link is registered and re-checked against the live page rather than linked from memory. How rules are written, tested and kept current →