PostgreSQL is an open-source object-relational database system with over 35 years of active development. It is known for its standards compliance, extensibility, and feature set that rivals commercial databases. Unlike MySQL, which prioritizes simplicity and speed for read-heavy workloads, PostgreSQL prioritizes correctness, feature completeness, and support for complex queries.
The database supports a wide range of data types beyond the standard SQL types — including JSON, JSONB, arrays, hstore (key-value), geometric types, and network address types. The JSONB type in particular has made PostgreSQL a viable alternative to document databases for applications that need flexible schema alongside relational data.
PostgreSQL is a strong default choice for most web application backends. The combination of relational integrity, JSON support, and full-text search means you can handle a wide range of data requirements without adding separate specialized databases. Many applications that start with a separate search service or document store find that PostgreSQL's built-in capabilities are sufficient.
For geospatial applications, the PostGIS extension turns PostgreSQL into a full geographic information system database. It is the standard choice for applications that need to store and query location data, calculate distances, or perform spatial analysis.
PostgreSQL is completely free and open source under the PostgreSQL License. Managed hosting is available from AWS (RDS/Aurora), Google Cloud SQL, Supabase, Neon, and others at various price points.