Technology
How do barcodes work?
A barcode stores a number as a pattern of black bars and white spaces of different widths. A scanner shines light at it, reads the reflected pattern, and converts it back into the number — which a computer looks up to find the product.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how barcodes works.
Step by step
- 1Bars and spaces of varying widths encode a number.
- 2A scanner reads how light reflects off the pattern.
- 3The pattern is decoded back into digits.
- 4A computer matches those digits to a product and price.
Frequently asked questions
- How does a barcode store information?
- As a pattern of black bars and white gaps of different widths that represent a number.
- How does a barcode scanner read it?
- It shines light on the code and measures the reflection, decoding the pattern into digits.
- What's the difference between a barcode and a QR code?
- Barcodes store data in 1D lines; QR codes use a 2D grid, holding much more information.