What this tool does
A searchable reference for every current AWS Region — its code, full name, geography, Availability Zone count, whether it needs to be opted into, and which partition it belongs to. Data is verified against AWS's own Regions table.
Opt-in regions
Regions launched after March 2019 aren't enabled by default — you have to turn them on for your account before you can use them. This matters for ARNs and API calls too: a request to an opt-in Region you haven't enabled fails, even with otherwise-correct credentials and permissions. If something is failing against a newer Region like ap-southeast-4 or eu-central-2, check whether the Region is actually enabled on the account before looking anywhere else.
Partitions
Almost every Region belongs to the standard aws partition. Two small, fully separate groups exist outside it: aws-us-gov (AWS GovCloud, US government workloads) and aws-cn (the China Regions, operated by local partners under a separate account system). Credentials, ARNs, and consoles don't cross between partitions — an ARN starting arn:aws-cn:... is meaningless to a standardaws account, and vice versa.
FAQ
Why does an ARN I have show an empty region field?
Some services are global and don't have a Region at all — IAM, S3 bucket-level actions, Route 53, and CloudFront are the common ones. See ARN Parser for a full breakdown of a specific ARN.
Does this show Availability Zone IDs or Local Zones?
No — this covers Regions only, with a total AZ count per Region. Local Zones and Wavelength Zones are separate, smaller extensions of a Region with their own naming scheme, not covered here.
Is this list live, pulled from an AWS API?
No — it's a static, periodically-updated reference, and nothing you search here leaves your browser. For your account's actual enabled Regions, check the AWS Console or run aws account list-regions in the CLI.