GTIN Validator & Check Digit Calculator — Free & Private

A free edge API by formatho.com, privacy-first developer tools.

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Free, no signup, runs entirely in your browser — your data never leaves your device.

🔓 Free🔒 Zero tracking🚫 No data collection⚡ Edge-fast

Usage — validate

curl "https://gtin-validator-formatho.filesformatho.workers.dev/api?gtin=4006381333931"

Checks structure (digits, length) and the GS1 mod-10 check digit; returns the expected digit, GTIN-14 padded form and type name.

Usage — compute a check digit

curl "https://gtin-validator-formatho.filesformatho.workers.dev/api?base=629104150021"

Give the first 7/11/12/13 digits, get the check digit that completes a valid GTIN.

Full parameter reference: /api endpoint.

Privacy-first: validation runs in-memory at the edge and is never logged or stored.

Full browser tool

Validate barcodes entirely client-side: GTIN Validator on formatho.com.

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