Barcode Validator (EAN/UPC)

About this tool

Check whether an EAN-13, EAN-8 or UPC-A barcode number is valid using its official check-digit formula.

Example

Input: 4006381333931

Output: Valid EAN-13

Privacy

This tool runs entirely in your browser. Your data is processed locally and never uploaded to a server.

How to use this tool

1. Paste a barcode number into the input field.
2. Choose EAN-13, EAN-8, or UPC-A if the tool asks you to specify the format.
3. Run the validation check.
4. Read the result to see whether the check digit is correct.

Step by step, what happens

1. The tool reads the barcode string you entered and checks that it uses the expected number of digits for the selected barcode type.
2. It separates the data digits from the final check digit and calculates the expected check digit using the official barcode validation rule.
3. The tool compares the calculated check digit with the one in your input.
4. It returns valid if they match, or invalid if they do not, so you can catch typos or bad data quickly.

Worked example

For example, if you want to verify a known valid UPC-A code before using it in a product record, you can test it directly.

Input: 036000291452

1. Paste 036000291452 into the validator as a UPC-A barcode.
2. The tool checks the length, then calculates the expected check digit from the first 11 digits.
3. It compares that result with the last digit in the input.

Tips and common mistakes

• Enter only the barcode digits, not spaces or labels, unless the tool explicitly allows formatting characters.
• Make sure you choose the right barcode type, because EAN-13, EAN-8, and UPC-A use different lengths.
• If a code fails validation, recheck the last digit first, since that is the check digit the tool verifies.
• A code can be the right length and still be invalid if even one digit is wrong.

Frequently asked questions