randarium
Test Data

Random ISBN Generator

Create realistic-looking ISBN values with proper checksums for testing libraries, bookstore systems, and import tools. Support both ISBN-10 and ISBN-13 formats with optional hyphenation.

Also known as: book isbn · isbn barcode

seeded · synthetic data

Presets

Output

No output yet — set your options and hit .
About this tool, tips & examples

What it does

The Random ISBN Generator produces synthetic ISBN-10 and ISBN-13 values with correctly computed check digits, hyphenated or plain — numbers that pass format validation while identifying no real book. Generate up to 1,000 per run, seeded for stable fixtures (presets for both formats and a large batch).

Common use cases

  • Library and bookstore systems — catalog fixtures, lookup flows, and import files with valid-format identifiers.
  • Import validation — the check digit is real math, so the accept path of ISBN validation gets genuine positives; corrupt a digit yourself for the negatives.
  • Book database seeding — ISBN columns for demo catalogs alongside the Book Title generator’s titles.
  • Parser testing — hyphenated vs plain formats exercise normalization code (ISBN-10’s X check character included).

Settings

  • Format — ISBN-10 (older, mod-11 checksum, may end in X) or ISBN-13 (current standard, EAN-compatible mod-10).
  • Include hyphens — grouped (978-0-…) or plain digits.
  • How many — 1 to 1,000 values, exportable as text, CSV, or JSON.
  • Seed — identical seed + settings = identical ISBNs.

Privacy note

Values are generated locally in your browser and never uploaded. They are fictional — not registered with any ISBN agency, assigned to no book — for testing only. Don’t print them on actual publications.

FAQ

Will these pass validation? Yes — checksums are computed with the standard algorithms, so format validators accept them. Lookups against real book databases will find nothing, which usefully tests that path too.

Why does ISBN-10 sometimes end in X? Its mod-11 checksum has 11 possible values; X represents 10. Any ISBN-10 parser must accept it — a classic missed edge case worth testing deliberately.

ISBN-10 or ISBN-13? ISBN-13 has been the standard since 2007; generate ISBN-10 when testing legacy data paths and format conversion. Retail barcodes (EAN/UPC) live in the Random Barcode generator.