Hexagonal segmentations of space have long been known for their advantages vis à vis squared partitions in discretizing spatial variables, be it natural phenomena or human-related features. However, readily available and easy-to-use tools to manipulate and interact with hexagonal rasters remain widely unavailable today. This article presents a first step to enable the use of hexagonal rasters in the GIS field. A format to encode cartographical hexagonal meshes as simple ASCII files is specified through a context-free grammar. Named HexASCII, this file format provides a simple means of storing and sharing such rasters. A set of simple tools based on the HexASCII format is presented, allowing their creation and basic interaction with traditional GIS software.