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ISSN Validator and Formatter
x402
ISSN Validator and Formatter is a paid API for AI agents from id-validators.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).
Validates the check digit of an ISSN (International Standard Serial Number) and returns it formatted with the standard hyphen separator.
Price / call$0.02
Success—
StatusUnknown
How this service works
Validate an ISSN (journal or serial number) check digit and format it with the hyphen.
Output
Returns a verdict (valid/invalid), a formatted ISSN string with hyphen, a normalised form, human-readable reasons explaining the validation outcome, a summary, and optional disclaimer and source metadata.
Example use cases
Journal metadata validation pipeline
“I'm ingesting a batch of academic journal records and need to verify that the ISSN 0028-0836 has a valid check digit and is properly formatted — can you check it?”
Publishing submission form check
“A user just submitted ISSN 03784266 on our submission form — can you validate its check digit and tell me what the correctly hyphenated version should be?”
Library catalog data cleanup
“We have the serial number 17518630 in our catalog without a hyphen — is it a valid ISSN and what's the standard formatted version?”
Technical details
Endpoint
GEThttps://id-validators.x402tookit.com/issn-check?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you specifically need to validate and format an ISSN (8-digit serial publication identifier). It is purpose-built for ISSN check-digit verification using the standard mod-11 algorithm, distinct from ISBN (books), ISIN (securities), LEI, or other identifier types handled by sibling endpoints on the same service.
Side effects
- Invalid or missing 'id' query parameter returns an error response
- ISSN with wrong number of digits fails validation with reasons explaining the format issue
- Incorrect check digit causes verdict to be invalid with explanation
- Non-numeric characters in unexpected positions cause format validation failure
- Network or service unavailability may result in HTTP errors
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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