diff --git a/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshaker.java b/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshaker.java
index 84c0a8d746..db364f5190 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshaker.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshaker.java
@@ -183,7 +183,7 @@ public final class PerMessageDeflateClientExtensionHandshaker implements WebSock
         }
 
         if ((requestedServerNoContext && !serverNoContext) ||
-                requestedServerWindowSize != serverWindowSize) {
+                requestedServerWindowSize < serverWindowSize) {
             succeed = false;
         }
 
diff --git a/codec-http/src/test/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshakerTest.java b/codec-http/src/test/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshakerTest.java
index d44244ed6e..3cc7492219 100644
--- a/codec-http/src/test/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshakerTest.java
+++ b/codec-http/src/test/java/io/netty/handler/codec/http/websocketx/extensions/compression/PerMessageDeflateClientExtensionHandshakerTest.java
@@ -90,7 +90,7 @@ public class PerMessageDeflateClientExtensionHandshakerTest {
 
         parameters = new HashMap<>();
         parameters.put(CLIENT_MAX_WINDOW, "12");
-        parameters.put(SERVER_MAX_WINDOW, "10");
+        parameters.put(SERVER_MAX_WINDOW, "8");
         parameters.put(CLIENT_NO_CONTEXT, null);
         parameters.put(SERVER_NO_CONTEXT, null);