Interleaved 2 of 5 bar code is one of the most widely used barcode symbology. Interleaved 2 of 5 bar code is developed on top of standard 2 of 5 barcode for higher data capacity.

Interleaved 2 of 5 encodes numeric-only data and is used primarily in logistics business.

A modulo 10 check digit is optional for Interleaved 2of5 barcode. Checksum calculation is the same as code 25. If you use Barcodesoft Interleaved 2of5 barcode software, you will find source code in VBA and C language of Interleaved 25 barcode checksum calculation.