Comparison \u00b7 Database
PostgreSQL vs MySQL: 2026 comparison
TL;DR: Pick PostgreSQL by default. Pick MySQL when an existing team has deep operational expertise in it, when you need its specific replication topology, or when you\’re extending a system that\’s already built on it.
See also: Research: PostgreSQL at scale
The headline difference
PostgreSQL is an object-relational database with a famously broad type system and a strong emphasis on standards compliance. MySQL is a relational database with a famously fast InnoDB storage engine and a long history of powering web-scale read workloads (Facebook, YouTube, Wikipedia were all originally MySQL). Both are battle-tested; the choice between them is now mostly about which has the features and ecosystem you actually need.
Feature scorecard
| Feature | PostgreSQL | MySQL |
|---|---|---|
| License | PostgreSQL Licence (BSD-like) | GPLv2 / commercial |
| JSON support | JSONB + JSON path, indexable | JSON type, limited indexing |
| Window functions | Full | Yes (since 8.0) |
| CTEs / recursive CTEs | Yes | Yes (since 8.0) |
| Arrays as a type | First-class | None |
| Vector / AI workloads | pgvector + pg_trgm | Add-on extensions only |
| Logical replication | Mature (PG 14+) | Mature (binlog-based, 20+ years) |
| Multi-master writes | Add-ons (BDR, Patroni) | Group Replication / InnoDB Cluster |
| Managed services | Aurora PG, AlloyDB, Neon, Supabase, RDS, CloudSQL | Aurora MySQL, RDS, CloudSQL, Azure DB |
| Default for new apps in 2026 | Yes | Only when there\’s a specific reason |
When MySQL is still the right answer
You have deep MySQL expertise on the team. Operating a database well is mostly about knowing its failure modes. A team that has been operating MySQL for ten years will run it better than they\’d run a fresh PostgreSQL deployment, full stop.
You\’re extending an existing MySQL system. Migrating between the two is doable but rarely worth the operational and feature-parity cost unless you have a specific feature need.
You need MySQL-specific replication topology. Particularly multi-source replication where multiple primaries fan into a single replica, MySQL handles this more naturally than PostgreSQL today.
The 2026 ecosystem
PostgreSQL\’s ecosystem has pulled ahead substantially in the past three years. The vector-search add-on (pgvector), the time-series extension (TimescaleDB), the geospatial extension (PostGIS), and the managed-service options (Aurora, AlloyDB, Neon, Supabase) have all matured. New AI applications default to PostgreSQL not because the engine is better at AI workloads but because the adjacent tooling (embeddings, semantic search, JSON document storage) is already there.
Frequently asked questions
Should a new application use PostgreSQL or MySQL in 2026?
PostgreSQL is the default recommendation for almost all new applications in 2026. It has a richer type system (including JSONB, arrays, ranges), stronger standards compliance, mature extensions (pgvector, PostGIS, TimescaleDB), and the managed-service ecosystem (Aurora, AlloyDB, Neon, Supabase, RDS) has closed the historical operational-complexity gap. MySQL is still the right answer when you need MySQL-specific replication or when an existing team has deep MySQL operational expertise.
Which is faster, PostgreSQL or MySQL?
Neither, in any meaningful general sense. MySQL with the InnoDB engine wins on simple key-lookup read workloads; PostgreSQL wins on complex queries with joins, CTEs, and window functions. At similar scale and tuning, query-shape and indexing matter more than the engine choice.
How do their replication stories compare?
MySQL has a more mature logical replication story (binlog-based, in production for two decades). PostgreSQL's logical replication caught up substantially in PG 14–17 and is now production-ready for read replicas, zero-downtime upgrades, and CDC pipelines. For physical replication (streaming WAL), PostgreSQL is excellent and operationally simpler than MySQL's group replication.
Which has better JSON support?
PostgreSQL by a wide margin. PostgreSQL has JSONB (binary, indexable, queryable with operators) plus JSON path support. MySQL has JSON type but lacks the same operator richness and indexing flexibility. If your data model is JSON-heavy, PostgreSQL is the answer.
Are they both fully open source?
Both yes — PostgreSQL under the permissive PostgreSQL License (BSD-like), MySQL under GPLv2 (owned by Oracle since the Sun acquisition). MySQL has commercial editions; PostgreSQL has no Pro/Enterprise tier from a single vendor.