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Atlas limits how many of each kind of component you can create, and the number of connections allowed to a database deployments. For clusters, the number of connections allowed is based on cluster tier. The following tables outline component and connection limits.
If any of these limits present a problem for your organization, contact Atlas support.
Shards in Single-region clusters
Cross-region network permissions for a Multi-Region Cluster
If any project's cluster spans more than 40 regions, you can't create a multi-region cluster in this project.
Electable Nodes per Replica Set or Shard
Config Server Tier (minimum and maximum)
Atlas sets the
limits for concurrent incoming connections based on the cluster tier and
class. Atlas connection limits apply per node. For
sharded clusters, Atlas connection limits apply per
mongos router. The number of
mongos routers is equal to
the number of replica set nodes across all shards.
Your read preference also contributes to the total number of connections Atlas can allocate for a given query.
Atlas reserves a small number of connections to each Atlas cluster for supporting Atlas services. To learn more about Atlas reserved connections, contact Atlas support.
While there is no hard limit on the number of collections in a single cluster, the performance of a cluster might degrade if it serves a large number of collections and indexes. Larger collections have a greater impact on performance.
The recommended maximum combined number of collections and indexes by Atlas cluster tier are as follows:
5,000 collections and indexes
M20 / M30
10,000 collections and indexes
100,000 collections and indexes
Database Users per Atlas Project
Atlas Users per Atlas Project
Atlas Users per Atlas Organization
API Keys per Atlas Organization
Access List Entries per Atlas Project
Users per Atlas Team
Teams per Atlas Project
Teams per Atlas Organization
Teams per Atlas User
Organizations per Atlas User
Linked Organizations per Atlas User
Clusters per Atlas Project
Projects per Atlas Organization
Custom MongoDB roles per Atlas Project
Assigned Roles per Database User
Hourly Billing per Atlas Organization
Total Network Peering Connections per Atlas Project
Pending Network Peering Connections per Atlas Project
AWS PrivateLink Addressable Targets per Region
Azure Private Link Addressable Targets per Region
Atlas limits the length of particular labels for components.
|||If you have peering-only mode enabled, the cluster name character limit is 23.|
||| Atlas uses the first 23 characters of a cluster name.
These characters must be unique within the containing project.
Cluster names with fewer than 23 characters can't end with a hyphen
|||(1, 2) Organization and Project names can include any Unicode letter or
number plus the following punctuation: |
Serverless instances have different limitations. To learn more, see Serverless Instance Limitations.
Multi-cloud deployments have different limitations. To learn more, see Multi-Cloud Deployment Limitations.