Quotas and Limits

EMQX Cloud sets default quotas (or limits) for each deployment and the default value of some of the quotas can be adjusted. The following tables show the default value of the quotas in different deployments and whether they can be adjusted. If you need to adjust the quotas, please contact us.

Serverless

Quotas	Default Value	Adjustable
Maximum internal authentication entries	2000	NO
Maximum internal ACL entries	2000	NO
Maximum message queue length	1000	NO
Session expiry time（MQTT 3.x）	2 hours	NO
Maximum retained messages	2000	NO
Maximum size of a retained message	1mb	NO
Retained message expiry interval	Never	NO
Client ID maximum length（MQTT 3.x）	23	NO
Client ID maximum length（MQTT 5.0）	256	NO
Maximum subscriptions for a single client	10	NO
TCP connect timeout	10s	NO
Number of deployments	1	YES
Number of subaccounts	20	NO

Dedicated and BYOC

Quotas	Default Value	Adjustable	Requires Deployment Restart
Maximum internal authentication entries	Session specification * 2	NO	-
Maximum internal ACL entries	Session specification * 2	NO	-
Maximum message queue length	1000	YES	NO
Session expiry time（MQTT 3.x）	2 hours	NO	NO
Maximum retained messages	Session specification * 10	YES	NO
Maximum size of a retained message	1mb	YES	NO
Retained message expiry interval	Never	YES	NO
Client ID maximum length（MQTT 3.x）	23	YES	YES
Client ID maximum length（MQTT 5.0）	256	YES	YES
API HTTP QPS	100/s	NO	-
TCP connect timeout	10s	YES	YES
Number of deployments	3	YES	NO
Number of subaccounts	20	NO	-