API under IPv4 and IPv6

Yes, Amazon API Gateway now supports dual-stack endpoints that can handle both IPv4 and IPv6 requests simultaneously. This feature is available for all endpoint types, including REST, HTTP, and WebSocket APIs, as well as custom domains.

API Gateway's dual-stack support allows you to configure your APIs to accept calls from both IPv4 and IPv6 clients. This means you can gradually transition from IPv4 to IPv6 environments without needing to switch everything at once. It helps organizations meet IPv6 compliance requirements and address IPv4 address scarcity issues.

The dual-stack functionality is available in all API Gateway commercial and AWS GovCloud (US) Regions. There's no additional charge for using this feature. When you create a new API or domain name, you can select the IP address type as either IPv4 only or dual-stack (IPv4 and IPv6).

It's important to note that if you're using resource policies, Lambda authorizers, or IAM policies that reference source IP addresses, you'll need to update these to accommodate IPv6 address formats.

This dual-stack approach helps future-proof your network infrastructure and expands your global reach, allowing you to serve clients regardless of whether they're using IPv4 or IPv6.
Sources
API Gateway launches support for dual-stack (IPv4 and IPv6) endpoints - AWS
Amazon API Gateway now supports dual-stack (IPv4 and IPv6) endpoints | AWS News Blog