Open Source
Products that are open source, allowing users to contribute to and modify the source code.
Updated June 14, 2026
Products that define this theme
A representative set of GIS Software products that exemplify Open Source, curated as a starting point for finding similar software.
Selected from G2's verified user reviews and ratings, then matched to this theme for relevance.
How Did G2 Choose These Open Source Products?
The 5 products shown represent a defining sample for the "Open Source" theme within GIS Software on G2 — not an exhaustive list. They are a curated starting point for discovering similar software.
- Sourced from products with verified G2 user reviews and ratings.
- Matched to this theme based on each product's described capabilities and fit, ordered by relevance.
- Rankings and inclusion are unbiased and are not influenced by vendor payment.
Refreshed weekly. Last updated: June 14, 2026.
QGIS is a free and open-source Geographic Information System (GIS) that enables users to visualize, edit, analyze, and publish geospatial information across various platforms, including Windows,...
OpenStreetMap (OSM) is a collaborative project that creates a free, editable map of the world, maintained by a community of volunteers. Established in 2004, OSM allows users to contribute and...
PostGIS is an open-source extension for the PostgreSQL relational database that enables the storage, indexing, and querying of geospatial data. By integrating geographic object support directly...
Apache Spatial Information System (SIS) is a free, open-source Java library designed for developing geospatial applications. It provides data structures for geographic features and associated...
GRASS is an open-source GIS package that provides tools and programs that can be sued for data management, image processing, graphic production, spatial modelling, and visualization of GIS data.