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GTIN, UPC & EAN Check Digit Calculator

Calculate and validate GTIN, UPC and EAN check digits

About This Tool

GTIN Check Digit Calculator computes or validates check digits for GTIN-8, UPC-12, EAN-13, GTIN-14, GLN, and SSCC using the standard mod-10 3/1 weights, with a step-by-step breakdown. Everything runs locally in your browser.

How to Use

  1. Paste digits (body or full code)
  2. Choose calculate or validate
  3. Review the detected type and steps
  4. Copy the result
  5. Try another code

Common Use Cases

  • Retail: Finish EAN/UPC barcodes before print
  • Warehouse: Validate SSCC or GTIN-14 labels
  • ERP: Double-check product identifiers
  • Learning: See the weighted sum worked out
  • QA: Catch typos before packaging goes to print

FAQ

Q1: How is the check digit calculated?

From the right, multiply digits by alternating weights 3 and 1, sum them, then the check digit is (10 βˆ’ sum mod 10) mod 10. Example: for 1234567 (GTIN-8 body) the weighted sum is 60, so the check digit is 0 β†’ 12345670.

Q2: Which code lengths are supported?

GTIN-8, UPC-12, EAN-13/GLN (13), GTIN-14, and SSCC (18).

Q3: Can I validate a full code?

Yes. Switch to validate mode and paste the complete number including the check digit.

Q4: Is my data uploaded?

No. Everything runs locally in your browser and is never uploaded.

Q5: Why was my input rejected?

Only digits are allowed, and the length must match a supported GTIN family.

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