EAN-13 Check Digit Calculator
A check digit is a single digit appended to a numerical identifier, like a barcode or account number, using a specific calculation method. Its purpose is to verify data accuracy during entry or transmission by recalculating the check digit at the receiving end and comparing it to the received one. A match indicates likely valid data, while a mismatch signals errors or corruption. Check digits are widely used in applications such as barcodes, credit card numbers, and ISBNs to enhance data accuracy and error detection.
The check digit is:
How does it work?
To calculate the check digit, we follow these guidelines:
- Sum all the digits in even positions and then multiply the result by 3.
- Add the sum of digits in odd positions (excluding the last digit, which is the check digit) to the calculated number.
- Divide this combined number by 10 and keep the remainder.
- If the remainder is not zero, subtract it from 10.
- The check digit is validated.
What do barcode numbers mean?
The numbers in a barcode convey essential information about the product or item it represents. A typical barcode includes a country code, which identifies the country where the product or manufacturer is registered, and a manufacturer code, indicating the specific company that produced the item. The product code follows, identifying the unique product within that manufacturer's range. Additionally, a check digit is often included to ensure data accuracy. When scanned, these numbers enable efficient inventory management, pricing, and tracking throughout the supply chain, facilitating accurate and streamlined retail operations and providing valuable information for logistics, sales, and stock management.
Which product is this barcode?
Checking a sneaker or streetwear barcode? Look it up to see the product it belongs to. Free, no account.
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Learn more
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