Telepen barcode symbology was designed to encode full ASCII character set without shift character. Wide to narrow ratio is fixed to 3:1. Telepen barcode has 2 different modes: alphanumeric mode and numeric-only mode.

Under both modes, Telepen barcode requires a start character, a check digit and a stop character. Telepen is very compact. It is able to encode 8 characters or 16 digits per inch.