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The following limitations apply to Atlas.
Atlas limits the number of the following items:
Components of particular type that you can create.
Connections allowed to a database deployment. For clusters, the number of connections allowed depends on the cluster tier.
Shard keys per project. Each Atlas project supports up to 40 unique shard keys. If you require multiple Global Clusters and might exceed this limit, deploy each additional Global Cluster in a separate project.
Serverless instances don't currently support all of the available Atlas features. MongoDB plans to add support for more configurations and capabilities on serverless instances over time. To learn more, see Serverless Instance Limitations.
Some commands have limitations on free clusters, or are unsupported on free clusters. Some commands have limitations on M10+ clusters, or are unsupported on M10+ clusters. Also, some commands are unsupported on serverless instances. To learn more, see Unsupported Commands in Atlas.
Atlas supports some commands only on free clusters. To learn more, see Commands Available Only in Free Clusters.