Mock AWS ARN Generator

How to use

1. 1️⃣
   Choose your options above
2. 2️⃣
   Click Generate
3. 3️⃣
   Copy your result

Detailed instructions

1. Select the AWS service you need ARNs for using the Service dropdown (e.g., S3, Lambda, DynamoDB).
2. Set the count field to the number of ARNs you want generated in one batch.
3. Click Generate to produce a list of correctly formatted fake ARNs for that service.
4. Copy individual ARNs or the full list and paste them into your policy JSON, Terraform variable file, or test fixture.
5. Re-run with a different service selected to generate ARNs for a second service without mixing formats.

Use Cases

• •Populating IAM policy JSON with S3 bucket ARNs before the buckets are provisioned in AWS
• •Seeding Jest or Pytest fixtures with Lambda execution role ARNs to test permission-branching logic
• •Filling Terraform variable files with placeholder RDS and DynamoDB ARNs during module scaffolding
• •Writing CloudFormation templates that reference SNS topic or SQS queue ARNs in a local dev stack
• •Generating safe ARN examples for public GitHub READMEs and internal AWS onboarding runbooks

Tips

• →Generate S3 ARNs separately from other services — S3 omits region and account-id, so mixing them in a policy array will look inconsistent.
• →When writing IAM resource arrays, generate one ARN per logical resource type to make your policy examples more realistic and easier to teach from.
• →Paste generated ARNs into cfn-lint or a JSON schema validator for your policy format before sharing — confirms structural correctness quickly.
• →For unit tests, store generated ARNs in a dedicated fixtures file and import them, rather than inlining them in each test, so swapping them out later is trivial.
• →Combine this generator with a mock account-ID list to simulate cross-account trust policies where the principal ARN must be from a different account than the resource ARN.
• →Avoid reusing the same fake ARN across multiple unrelated documents — regenerate fresh ones each time to prevent readers assuming a specific value is canonical.

FAQ