Description
Check whether a 13-digit identifier starts with 978 or 979, without validating a complete ISBN.
Identifier validation can involve several distinct questions: whether text has the expected shape, whether a checksum is consistent, and whether an authority actually assigned the identifier. Formatting and field extraction address narrower questions. Each result must be read according to the particular property the tool checks.
Check whether a 13-digit identifier starts with 978 or 979, without validating a complete ISBN.
When to use this tool
Use ISBN-13 EAN Prefix Member Check when you need the particular shape, formatting, field, or checksum property as one explicit stage in an identifier workflow.
How to use the tool and how it works
- Enter identifier. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read bookland, prefix. Inspect bookland before interpreting the associated values.
Require exactly 13 ASCII digits. Return prefix as the first three digits and bookland when it equals 978 or 979.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| identifier | Identifier | Required. Text; maximum UTF-16 length 8192. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| bookland | Bookland | Required. Boolean. |
| prefix | Prefix | Required. Text; maximum UTF-16 length 8192. |
{
"input": {
"identifier": "9780306406157"
},
"output": {
"bookland": true,
"prefix": "978"
}
}Limitations and assumptions
- This is a prefix membership check, not full ISBN validation. It does not check checksum, allocation ranges or exclusions, title metadata, or whether a particular 979-prefixed identifier is an ISBN.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
Alternative or Complementary methods
Use a complete format and checksum validator when required, then consult the issuing registry or verification process for assignment and identity. Preserve meaningful leading zeros as text.
References
Similar or alternative tools
- validate/isbn
Validate ISBN-10 and Bookland-prefixed ISBN-13 identifiers after removing spaces and hyphens, reject the 979-0 ISMN range, and convert valid 978-prefixed identifiers between formats.
- ISBN Check Digit Transposition Witness
Witness checksum detection for an ISBN-13 digit transposition; registration and prefix allocation are not checked.