ISSN Hyphen Position Check Tool

Description

Check exactly four ASCII digits, a hyphen, three digits, and one digit or uppercase X.

An identifier can have the expected character layout and still contain an incorrect check digit or refer to no assigned record. Layout screening is an early data-cleaning step rather than an authoritative identifier lookup.

Check exactly four ASCII digits, a hyphen, three digits, and one digit or uppercase X.

When to use this tool

Use ISSN Hyphen Position Check when you need to check the supported identifier spelling before a separate check-digit or assignment check.

How to use the tool and how it works

Enter text. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read layoutValid. Inspect layoutValid before interpreting the associated values.

Check exactly four ASCII digits, a hyphen, three digits, and one digit or uppercase X. Return layoutValid.^[1]

Input field	Meaning and units	Accepted input
text	Supplied text; only the transformations stated above are applied.	Required. Text; maximum UTF-16 length 8192.

Output field	Interpretation	Returned shape
layoutValid	Layout Valid	Required. Boolean.

json

{
  "input": {
    "text": "1234-567X"
  },
  "output": {
    "layoutValid": true
  }
}

Limitations and assumptions

This checks ISSN layout only, not its check digit, assignment, publication identity, or lowercase x.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.

Alternative or Complementary methods

Use a dedicated checksum validator and the issuing registry when identifier validity or assignment matters.

References

Calculation and input contract: validate/issn-hyphen-position-check — tool.io

Similar or alternative tools

validate/issn
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