TEKLYNX Blog: The Human Readable

What Is a Check Digit? The Key to Barcode Accuracy & Validation

BY: TRAVIS WAYNE / DATE: 19/06/2025 / TOPICS: OTOMOTİV, YİYECEK VE İÇECEK, SAĞLIK HİZMETİ, ÜRETİM, TIBBİ CİHAZ, ECZACILIK, PERAKENDE, SEVKİYAT VE TESLİM ALMA, DEPOLAMA VE DAĞITIM, BARCODE BASICS, REGULATORY COMPLIANCE

What is a check digit? Simply put, a check digit is an extra number added to a barcode to help detect errors. Barcode check digits are calculated using algorithms during both barcode creation and scanning. If the scanned check digit matches the created check digit, the barcode was scanned correctly.

Check digits are foundational to barcode data integrity, validation, and quality. In this blog, we’ll dive into what check digits are, how they work, and why they’re important.