ISSN Validator
Free online ISSN validator. Verify ISSN-8 modulus 11 checksums, convert between ISSN and ISSN-EAN-13 (977 prefix) barcodes, and catch data-entry errors.
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What is ISSN Validator?
The ISSN Validator is a free online tool that checks whether an International Standard Serial Number (ISSN) is structurally correct by verifying its modulus 11 check digit. It also converts valid codes between the 8-character ISSN form and the 13-digit ISSN-EAN-13 barcode form that starts with the 977 prefix.
Key Benefits
- Catches typos and data-entry errors before they propagate into catalogs or subscriptions
- Keeps publication databases consistent by converting between ISSN-8 and ISSN-EAN-13
- Works offline and client-side, protecting sensitive bibliographic data
- Accepts hyphenated and spaced input without manual cleanup
Common Use Cases
- •Librarians verifying ISSNs when cataloging serials and periodicals
- •Publishers and print shops checking ISSN and barcode consistency on magazine covers
- •Subscription agencies validating serial identifiers before processing orders
- •Developers building publication databases who need clean, normalized ISSNs
- •Researchers double-checking journal identifiers in citations and reference lists
How to Use the ISSN Validator
- Enter the ISSN: Type or paste the ISSN into the input field. Hyphens and spaces are allowed and will be normalized automatically.
- Choose a format (optional): Leave the format on Auto for automatic detection, or force ISSN-8 / ISSN-EAN-13 if you need a specific interpretation.
- Read the result: A green panel confirms a valid ISSN and shows the format; a red panel flags an invalid length or checksum mismatch, including the expected check digit.
- Convert or copy: For valid codes, use the copy buttons to grab the hyphenated ISSN or its converted ISSN-EAN-13 / ISSN-8 equivalent.
Key Features
- Validates ISSN-8 with the official modulus 11 checksum (check digit 0-9 or X)
- Automatic format detection with optional ISSN-8 / ISSN-EAN-13 override
- Bi-directional conversion between ISSN-8 and 977-prefix EAN-13 barcodes
- Shows the expected check digit when validation fails
- Tolerates hyphens and spaces in input automatically
- 100% client-side processing for full privacy
Frequently Asked Questions
What is the difference between ISSN and ISSN-EAN-13?
ISSN is the 8-character standard serial identifier (7 digits plus a modulus 11 check digit that can be 0-9 or X). ISSN-EAN-13 is the 13-digit barcode form printed on magazine covers: it adds the 977 prefix, the 7 ISSN digits, 2 filler digits (usually 00), and a GTIN-13 check digit.
Can this tool convert ISSN to the EAN-13 barcode?
Yes. For any valid ISSN-8, the tool computes the ISSN-EAN-13 by prepending 977, appending the 00 filler digits, and calculating the GTIN-13 check digit. It also converts a valid 977-prefix EAN-13 back to its ISSN-8 equivalent.
Why does my ISSN show as invalid?
The most common causes are a typo in the digits, a wrong check digit, or input that is not exactly 8 characters (ISSN-8) or 13 digits (EAN-13) after removing hyphens. The tool shows the expected check digit to help you spot the mistake.
Does this tool send my data anywhere?
No. All validation and conversion runs entirely in your browser. No ISSN or personal data is ever transmitted to a server, so it is safe to use even with sensitive bibliographic records.