CleanUtils

GTIN, EAN, and UPC Check-Digit Validator

Paste product identifiers to verify check digits or calculate the missing final digit before feed upload.

Also useful for: ean check digit calculator upc validator gtin check digit GTIN/EAN/UPC Check-Digit Validator

GTIN/EAN/UPC Check-Digit Validator

Runs in your browser. Inputs are not uploaded.
Input
Results 
Summary: 3 codes checked. 1 warning.

Stats
- Codes: 3

Issues
- Warning, line 3: 01234567890 is missing the final check digit. Complete UPC-A / GTIN-12 code: 012345678905.

Output
036000291452: valid UPC-A / GTIN-12 (expected check digit 2)
4006381333931: valid EAN-13 / GTIN-13 (expected check digit 1)
01234567890: missing check digit for UPC-A / GTIN-12. Complete code: 012345678905

GTIN/EAN/UPC Check-Digit Validator Example Run

Validate a UPC and complete a missing check digit.

Sample inputs
036000291452
4006381333931
01234567890

Generated result
Summary: 3 codes checked. 1 warning.

Stats
- Codes: 3

Issues
- Warning, line 3: 01234567890 is missing the final check digit. Complete UPC-A / GTIN-12 code: 012345678905.

Output
036000291452: valid UPC-A / GTIN-12 (expected check digit 2)
4006381333931: valid EAN-13 / GTIN-13 (expected check digit 1)
01234567890: missing check digit for UPC-A / GTIN-12. Complete code: 012345678905

What the GTIN/EAN/UPC Check-Digit Validator Checks

  • GTIN length detection

    The tool recognizes GTIN-8, UPC-A/GTIN-12, EAN-13/GTIN-13, and GTIN-14 lengths.

  • Modulo check digit math

    Check digits are recalculated from the preceding digits and compared with the supplied final digit.

  • Missing final digit

    When a code is one digit short, the tool calculates the expected check digit and complete code.

  • Non-digit cleanup

    Spaces and punctuation are stripped before validation so copied spreadsheet values still work.

  • Assignment caveat

    The checksum proves mathematical validity, not GS1 registration or marketplace acceptance.

GTIN/EAN/UPC Check-Digit Validator Questions

  • Q: Does the GTIN/EAN/UPC check-digit validator upload my barcode numbers? A: No. Inputs are processed in your browser, and pasted content is not sent to analytics or a server.
  • Q: What should I paste into the GTIN/EAN/UPC check-digit validator? A: Paste one GTIN, EAN, or UPC value per line. Spaces and hyphens are okay.
  • Q: What can I copy or download? A: You can copy the validation report with detected type, expected check digit, and completed missing-digit values.
  • Q: What does the GTIN/EAN/UPC check-digit validator not verify? A: It does not look up ownership, product identity, country prefix meaning, or whether a marketplace will accept the identifier.

Related Tools

Updates

  • v1.0.0 New 2026-05-17: Initial GTIN/EAN/UPC checksum validation and missing-check-digit calculator added.

Use GTIN/EAN/UPC Check-Digit Validator with an LLM

Copy the prompt or pass the llms.txt contract link to your assistant.

Prompt 
Use the CleanUtils GTIN/EAN/UPC Check-Digit Validator tool for this request.
Tool contract: https://cleanutils.com/business-tools/gtin-ean-upc-check-digit-validator/llms.txt

Read the llms.txt contract, ask me for any missing required input, then follow the contract exactly. If the contract includes JavaScript, run `runCleanUtilsTool(userInput)` in a sandboxed JavaScript runtime and return the result with any warnings or errors.
llms.txt https://cleanutils.com/business-tools/gtin-ean-upc-check-digit-validator/llms.txt