---
title: "What is EDNS Client Subnet (ECS)? - qg58ahy9ww549ax"
description: "Quad9's 9.9.9.11 service supports ECS."
date: "2026-06-10T17:52:20+00:00"
language: "en-US"
canonical_url: "https://quad9.faceliftdesigns.com/docs/what-is-edns-client-subnet-ecs/"
source_url: "https://quad9.faceliftdesigns.com/docs/what-is-edns-client-subnet-ecs/"
content_type: "text/markdown"
---