ScyllaDB

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.

Couchbase

couchbase.com

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

FerretDB

FerretDB/FerretDB

Rising

Open-source MongoDB-compatible database built on Postgres with the DocumentDB extension.

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.