IAM and Amazon STS quotas - Amazon Identity and Access Management
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China.

IAM and Amazon STS quotas

Amazon Identity and Access Management (IAM) and Amazon Security Token Service (STS) have quotas that limit the size of objects. This affects how you name an object, the number of objects you can create, and the number of characters you can use when you pass an object.

Note

To get account-level information about IAM usage and quotas, use the GetAccountSummary API operation or the get-account-summary Amazon CLI command.

IAM name requirements

IAM names have the following requirements and restrictions:

  • Policy documents can contain only the following Unicode characters: horizontal tab (U+0009), linefeed (U+000A), carriage return (U+000D), and characters in the range U+0020 to U+00FF.

  • Names of users, groups, roles, policies, instance profiles, and server certificates must be alphanumeric, including the following common characters: plus (+), equal (=), comma (,), period (.), at (@), underscore (_), and hyphen (-).

  • Names of users, groups, roles, and instance profiles must be unique within the account. They are not distinguished by case, for example, you cannot create groups named both ADMINS and admins.

  • The external ID value that a third party uses to assume a role must have a minimum of 2 characters and a maximum of 1,224 characters. The value must be alphanumeric without white space. It can also include the following symbols: plus (+), equal (=), comma (,), period (.), at (@), colon (:), forward slash (/), and hyphen (-). For more information about the external ID, see How to use an external ID when granting access to your Amazon resources to a third party.

  • Path names must begin and end with a forward slash (/).

  • Policy names for inline policies must be unique to the user, group, or role they are embedded in. The names can contain any Basic Latin (ASCII) characters minus the following reserved characters: backward slash (\), forward slash (/), asterisk (*), question mark (?), and white space. These characters are reserved according to RFC 3986.

  • User passwords (login profiles) can contain any Basic Latin (ASCII) characters.

  • Amazon account ID aliases must be unique across Amazon products, and must be alphanumeric following DNS naming conventions. An alias must be lowercase, it must not start or end with a hyphen, it cannot contain two consecutive hyphens, and it cannot be a 12-digit number.

For a list of Basic Latin (ASCII) characters, go to the Library of Congress Basic Latin (ASCII) Code Table.

IAM object quotas

Quotas, also referred to as limits in Amazon, are the maximum values for the resources, actions, and items in your Amazon account. Use Service Quotas to manage your IAM quotas. You can request an increase to default quotas for adjustable IAM quotas. Requests up to the maximum quota are automatically approved and are completed within a few minutes.

To request a quota increase, sign in to the Amazon Web Services Management Console and open the Service Quotas console at https://console.amazonaws.cn/servicequotas/. In the navigation pane, choose Amazon services. On the navigation bar, choose the US East (N. Virginia) Region. Then search for IAM. Choose Amazon Identity and Access Management (IAM), choose a quota, and follow the directions to request a quota increase. For more information, see Requesting a Quota Increase in the Service Quotas User Guide.

The following quotas are adjustable.

Default quotas for IAM entities
Resource Default quota Maximum quota
Role trust policy length 2048 characters 4096 characters
Customer managed policies in an Amazon account 1500 5000
Groups in an Amazon account 300 500
Roles in an Amazon account 1000 5000
Managed policies attached to an IAM role 10 20
Managed policies attached to an IAM user 10 20
Virtual MFA devices (assigned or unassigned) in an Amazon account Equal to the user quota for the account Not applicable
Instance profiles in an Amazon account 1000 5000
Server certificates stored in an Amazon account 20 1000

You cannot request an increase for the following quotas.

Quotas for IAM entities
Resource Quota
Access keys assigned to an IAM user 2
Access keys assigned to the Amazon Web Services account root user 2
Aliases for an Amazon account 1
Groups an IAM user can be a member of 10
IAM users in a group Equal to the user quota for the account
Identity providers (IdPs) associated with an IAM SAML provider object 10
Keys per SAML provider 10
Login profiles for an IAM user 1
Managed policies attached to an IAM group 10
OpenId Connect identity providers per Amazon account 100
Permissions boundaries for an IAM user 1
Permissions boundaries for an IAM role 1
MFA devices in use by an IAM user 1
MFA devices in use by the Amazon Web Services account root user 1
Roles in an instance profile 1
SAML providers in an Amazon account 100
Signing certificates assigned to an IAM user 2
SSH public keys assigned to an IAM user 5
Tags that can be attached to a customer managed policy 50
Tags that can be attached to an instance profile 50
Tags that can be attached to an Open ID Connect (OIDC) identity provider 50
Tags that can be attached to an IAM role 50
Tags that can be attached to a SAML identity provider 50
Tags that can be attached to a server certificate 50
Tags that can be attached to an IAM user 50
Tags that can be attached to a virtual MFA device 50
Users in an Amazon account 5000 (If you need to add a large number of users, consider using temporary security credentials.)
Versions of a managed policy that can be stored 5

IAM Access Analyzer quotas

For IAM Access Analyzer quotas, see IAM Access Analyzer Quotas.

IAM and STS character quotas

The following are the maximum character counts and size quotas for IAM and Amazon STS. You cannot request an increase for the following quotas.

Description Quota
Path 512 characters
User name 64 characters
Group name 128 characters
Role name 64 characters
Important

If you intend to use a role with the Switch Role feature in the Amazon Web Services Management Console, then the combined Path and RoleName cannot exceed 64 characters.

Tag key 128 characters

This character quota applies to tags on IAM resources and session tags.

Tag value 256 characters

This character quota applies to tags on IAM resources and session tags.

Tag values can be empty which means tag values can have a length of 0 characters.

Instance profile name 128 characters

Unique IDs created by IAM

128 characters. For example:

  • User IDs that begin with AIDA

  • Group IDs that begin with AGPA

  • Role IDs that begin with AROA

  • Managed policy IDs that begin with ANPA

  • Server certificate IDs that begin with ASCA

Note

This is not intended to be an exhaustive list, nor is it a guarantee that IDs of a certain type begin only with the specified letter combination.

Policy name 128 characters
Password for a login profile 1–128 characters
Alias for an Amazon account ID 3–63 characters
Role session name 64 characters
Role session duration

12 hours

When you assume a role from the Amazon CLI or API, you can use the duration-seconds CLI parameter or the DurationSeconds API parameter to request a longer role session. You can specify a value from 900 seconds (15 minutes) up to the maximum session duration setting for the role, which can range 1–12 hours. If you don't specify a value for the DurationSeconds parameter, your security credentials are valid for one hour. IAM users who switch roles in the console are granted the maximum session duration, or the remaining time in the IAM user's session, whichever is less. The maximum session duration setting does not limit sessions assumed by Amazon services. To learn how to view the maximum value for your role, see View the maximum session duration setting for a role.

Role session policies
  • The size of the passed JSON policy document and all passed managed policy ARN characters combined cannot exceed 2,048 characters.

  • You can pass a maximum of 10 managed policy ARNs when you create a session.

  • You can pass only one JSON policy document when you programmatically create a temporary session for a role or federated user.

  • Additionally, an Amazon conversion compresses the passed session policies and session tags into a packed binary format that has a separate quota. The PackedPolicySize response element indicates by percentage how close the policies and tags for your request are to the upper size quota.

  • We recommend that you pass session policies using the Amazon CLI or Amazon API. The Amazon Web Services Management Console might add additional console session information to the packed policy.

Role session tags
  • Session tags must meet the tag key quota of 128 characters and the tag value quota of 256 characters.

  • You can pass up to 50 session tags.

  • An Amazon conversion compresses the passed session policies and session tags into a packed binary format that has a separate quota. You can pass session tags using the Amazon CLI or Amazon API. The PackedPolicySize response element indicates by percentage how close the policies and tags for your request are to the upper size quota.

For inline policies You can add as many inline policies as you want to an IAM user, role, or group. But the total aggregate policy size (the sum size of all inline policies) per entity cannot exceed the following quotas:
  • User policy size cannot exceed 2,048 characters.

  • Role policy size cannot exceed 10,240 characters.

  • Group policy size cannot exceed 5,120 characters.

Note

IAM does not count white space when calculating the size of a policy against these quotas.

For managed policies
  • The size of each managed policy cannot exceed 6,144 characters.

Note

IAM does not count white space when calculating the size of a policy against this quota.