IAM and Amazon STS quotas - Amazon Identity and Access Management
IAM name requirementsIAM object quotasIAM Access Analyzer quotasIAM Roles Anywhere quotasSTS request quotasIAM and STS character limits
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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, server certificates, and paths must be alphanumeric, including the following common characters: plus (+), equals (=), comma (,), period (.), at (@), underscore (_), and hyphen (-). Path names must begin and end with a forward slash (/).

  • Names of users, groups, roles, and instance profiles must be unique within the account. They aren’t distinguished by case, for example, you can't 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 Access to Amazon Web Services accounts owned by third parties.

  • Policy names for inline policies must be unique to the user, group, or role they're embedded in. The names can contain any Basic Latin (ASCII) characters except for the following reserved characters: backward slash (\), forward slash (/), asterisk (*), question mark (?), and white space. These characters are reserved according to RFC 3986, section 2.2.

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

  • Amazon Web Services 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 can't contain two consecutive hyphens, and it can't 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 Web Services account. Use Service Quotas to manage your IAM quotas.

For the list of IAM service endpoints and service quotas, see Amazon Identity and Access Management endpoints and quotas in the Amazon Web Services General Reference.

To request a quota increase

  1. Follow the sign-in procedure appropriate to your user type as described in the topic How to sign in to Amazon in the Amazon Sign-In User Guide to sign in to the Amazon Web Services Management Console.

  2. Open the Service Quotas console.

  3. In the navigation pane, choose Amazon services.

  4. On the navigation bar, choose the US East (N. Virginia) Region. Then search for IAM.

  5. 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.

You can request an increase to default quotas for adjustable IAM quotas. Requests up to the maximum quota are automatically approved and completed within a few minutes.

The following table lists the resources for which quota increases area can be automatically approved.

Resource Default quota Maximum quota
Customer managed policies per account 1500 5000
Groups per account 300 500
Instance profiles per account 1000 5000
Managed policies per role 10 20
Managed policies per user 10 20
Managed policies per group 10 10
Role trust policy length 2048 characters 4096 characters
Roles per account 1000 5000
Server certificates per account 20 1000

IAM Access Analyzer quotas

For the list of IAM Access Analyzer service endpoints and service quotas, see IAM Access Analyzer endpoints and quotas in the Amazon Web Services General Reference.

IAM Roles Anywhere quotas

For the list of IAM Roles Anywhere service endpoints and service quotas, see Amazon Identity and Access Management Roles Anywhere endpoints and quotas in the Amazon Web Services General Reference.

STS request quotas

The Amazon STS service has a default request quota of 600 requests per second per account, per region. This quota is shared across the following STS requests that are made using Amazon credentials:

  • AssumeRole

  • DecodeAuthorizationMessage

  • GetAccessKeyInfo

  • GetCallerIdentity

  • GetFederationToken

  • GetSessionToken

For example, if an Amazon Web Services account makes 100 GetCallerIdentity requests per second and 100 AssumeRole calls per second in the same region, that account is consuming 200 of its available 600 STS requests per second for that region.

For cross-account AssumeRole requests, only the account making the AssumeRole request impacts the STS quota. The target account does not have any of it’s quota consumed.

Note

Requests to Amazon STS by Amazon service principals, such as those used to assume roles for use with an Amazon service, do not consume STS request per second quota in your accounts.

To request an increase to STS request quotas, please open a ticket with Amazon support.

IAM and STS character limits

The following are the maximum character counts and size limits for IAM and Amazon STS. You can't request an increase for the following limits.

Description Limit
Alias for an Amazon Web Services account ID 3–63 characters
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 can't exceed the following limits:

  • User policy size can't exceed 2,048 characters.

  • Role policy size can't exceed 10,240 characters.

  • Group policy size can't exceed 5,120 characters.

Note

IAM doesn't count white space when calculating the size of a policy against these limits.
For managed policies

  • The size of each managed policy can't exceed 6,144 characters.

Note

IAM doesn't count white space when calculating the size of a policy against this limit.
Group name 128 characters
Instance profile name 128 characters
Password for a login profile 1–128 characters
Path 512 characters
Policy 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 can't exceed 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 user's session, whichever is less. The maximum session duration setting doesn't limit sessions assumed by Amazon services. To learn how to view the maximum value for your role, see Update the maximum session duration for a role.

Role session name 64 characters
Role session policies

  • The size of the passed JSON policy document and all passed managed policy ARN characters combined can't 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 limit. The PackedPolicySize response element indicates by percentage how close the policies and tags for your request are to the upper size limit.

  • 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 limit of 128 characters and the tag value limit 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 limit. 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 limit.
SAML authentication response base64 encoded 100,000 characters

This character limit applies to assume-role-with-saml CLI or AssumeRoleWithSAML API operation.
Tag key 128 characters

This character limit applies to tags on IAM resources and session tags.
Tag value 256 characters

This character limit 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.

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 isn't intended to be an exhaustive list, nor is it a guarantee that IDs of a certain type begin only with the specified letter combination.
User name 64 characters