At a glance
| Data model | Distributed tables usable as key-value or SQL (Ignite 3); key-value caches with SQL (Ignite 2) |
| Query language | SQL (Calcite engine) via JDBC, ODBC and native APIs; key-value APIs |
| Consistency model | Strongly consistent mode with Raft consensus (Ignite 3) |
| Replication | Partition replicas with Raft-based replication groups (Ignite 3) |
| Partitioning or sharding | Automatic partitioning; distribution zones in Ignite 3, affinity functions in Ignite 2 |
| Transactions | ACID, MVCC-based, Serializable isolation available (Ignite 3) |
| Deployment and cloud availability | Self-managed (ZIP archive or Docker image); no ASF managed service |
| Licensing | Apache 2.0, free; commercial GridGain 9 based on Ignite 3 |
| Release lines | Ignite 3.1.0 (October 2025) and Ignite 2.17.0 (February 2025) |
Apache Ignite suits Java and .NET teams that need a distributed in-memory data layer with SQL, transactions and colocated compute, free under Apache 2.0. Decide early between Ignite 3, the redesigned line with a schema-first model and Raft-based consistency, and Ignite 2, the long-established line with a wider client and integration set, because code and configuration do not carry over directly.
Overview
Apache Ignite is a distributed database that keeps data in memory, optionally with persistence, across a cluster of nodes, and lets applications run computations next to the data. Ignite 3, first released as 3.0.0 in February 2025, is schema-driven: tables are defined with DDL and reached through a Table API, a key-value view, SQL (JDBC, ODBC and native SQL APIs for Java, C# and C++) and a Compute API. It uses Raft-based consensus, MVCC transactions that can run at Serializable isolation in its strongly consistent mode, a Calcite-based SQL engine, pluggable storage engines (in-memory and RocksDB by default), and a CLI and REST API for management.
Ignite 2 (2.17.0, February 2025) is the older line: a key-value cache API with SQL, native persistence, snapshots and change data capture, continuous queries, a compute grid, machine learning libraries and thin clients for Java, .NET, C++, Python, PHP and Node.js. Ignite 3 changes configuration from XML to HOCON or JSON and replaces affinity functions with distribution zones, so Ignite 2 code and configuration need migration. GridGain Systems, which donated the original code to the ASF in 2014, contributes to Ignite and sells GridGain 9, an enterprise platform based on Ignite 3.
Key features
- In-memory storage with optional persistence across a distributed cluster
- SQL with JDBC and ODBC drivers, using a Calcite-based engine
- ACID transactions with MVCC, Serializable isolation in Ignite 3's strongly consistent mode
- Raft-based consensus and schema-first tables in Ignite 3
- Distributed compute API to run code where the data lives
- Key-value and Table APIs for Java, .NET and C++ (and more thin clients on Ignite 2)
- CLI and REST API for cluster management (Ignite 3)
Integrations and ecosystem
Pros and cons
Pros
- Free Apache 2.0 licence under ASF governance
- Combines in-memory speed, SQL, transactions and colocated compute in one system
- Ignite 3 brings Raft consensus, MVCC and a Calcite SQL engine
- Commercial support and an enterprise distribution available from GridGain
Cons
- Two incompatible release lines: Ignite 2 code and XML configuration cannot be reused directly on Ignite 3
- Ignite 3 has fewer thin clients documented than Ignite 2
- Release cadence is slow: the latest versions date from 2025
- No managed service from the project; you operate the cluster
Pricing
Apache Ignite (both the 3.x and 2.x lines) is free open source software under Apache 2.0 from the Apache Software Foundation, with no paid edition from the project. Commercial support and enterprise features are sold separately by GridGain Systems, whose GridGain 9 platform is based on Ignite 3 and requires a GridGain licence file (a Community Edition or evaluation licence is available); GridGain prices were not reviewed for this profile.
Pricing checked on the vendor's official page on 7 November 2026. Prices change; confirm before buying.
Who it is best for
Java and .NET teams that need a free distributed in-memory data layer with SQL, transactions and colocated computation, and can operate a cluster themselves.
Typical use cases
- In-memory data grid or cache layer in front of relational databases
- Low-latency transactional processing for trading, payments and telecom systems
- Colocated distributed computation over large in-memory datasets
- Shared operational data hub for microservices with SQL access
Who should look elsewhere
- Teams that only need a cache in front of a database, where Redis is simpler to run.
- Teams wanting a fully managed distributed SQL service: consider CockroachDB or YugabyteDB cloud offerings.
Verdict
Apache Ignite is a capable free option for a distributed in-memory database with SQL and compute, and Ignite 3 modernises its consistency and SQL layers. The split between Ignite 2 and Ignite 3 is the main planning risk: new projects should start on Ignite 3 unless they need an Ignite 2-only feature, and teams wanting vendor support should evaluate GridGain alongside it.
Frequently asked questions
Should I use Ignite 3 or Ignite 2?
Ignite 3 is the redesigned line (3.0.0 in February 2025, 3.1.0 in October 2025) with schema-first tables, Raft consensus, MVCC transactions and a Calcite SQL engine. Ignite 2 (2.17.0) has a broader set of thin clients and features such as machine learning. Ignite 2 code cannot be reused directly, so pick a line before you build.
What is the relationship between Apache Ignite and GridGain?
GridGain Systems created the original code and donated it to the Apache Software Foundation in 2014. It contributes to Ignite and sells GridGain 9, an enterprise platform based on Ignite 3 that requires a GridGain licence.
Is Apache Ignite free?
Yes. Both lines are released by the ASF under the Apache 2.0 licence. You pay only for infrastructure, or for commercial support if you buy it from a vendor such as GridGain.
Sources
- Apache Ignite downloads
- Apache Ignite 3 documentation
- Ignite 3: migration from Ignite 2
- Apache Ignite 2 documentation
- apache/ignite-3 repository
- GridGain press release on Apache Ignite 3.0 (24 February 2025)
Checked November 2026.
Listed in: NoSQL & Distributed Databases.
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