diff --git a/examples/echo/echo.go b/examples/echo/echo.go
index e5738ac..dafc88a 100644
--- a/examples/echo/echo.go
+++ b/examples/echo/echo.go
@@ -66,7 +66,7 @@ func main() {
 				v = "Hello, " + v
 			}
 
-			ctx.Header().Set("Etag", `W/"foo"`)
+			ctx.Header().Set("ETag", `W/"foo"`)
 			ctx.WriteModel(http.StatusOK, EchoResponse{
 				Value: v,
 				Foo:   input.Foo,