FerretDB

MongoDB

mongodb/mongo

Popular

The most popular document database, with flexible JSON-like documents, aggregation and Atlas cloud.

Amazon DynamoDB

aws.amazon.com

Popular

AWS's serverless key-value and document database with single-digit millisecond latency at any scale.

Apache Cassandra

apache/cassandra

Popular

Masterless wide-column database for massive write throughput and multi-datacenter availability.

Azure Cosmos DB

azure.microsoft.com

Azure's globally distributed multi-model database with NoSQL, MongoDB and Cassandra APIs.

Cloud Firestore

firebase.google.com

Google's serverless document database with realtime sync and offline support for mobile and web apps.

ScyllaDB

scylladb/scylladb

Cassandra- and DynamoDB-compatible wide-column database in C++ with much lower tail latency.

Couchbase

couchbase.com

Distributed JSON document database with SQL++ queries, caching and mobile sync.

Apache CouchDB

apache/couchdb

Document database with HTTP/JSON API and multi-master replication designed for offline sync.

Apache HBase

apache/hbase

Legacy

Hadoop-era wide-column store modeled on Bigtable; still in big installs but rarely chosen for new projects.