diff --git a/lib/Plack/Server/Standalone.pm b/lib/Plack/Server/Standalone.pm
index 6bdb759a6..8bb8fee92 100644
--- a/lib/Plack/Server/Standalone.pm
+++ b/lib/Plack/Server/Standalone.pm
@@ -117,6 +117,7 @@ sub handle_connection {
         "Date: @{[HTTP::Date::time2str()]}\015\012",
         "Server: Plack-Server-Standalone/$Plack::VERSION\015\012",
     );
+    my $has_cl = Plack::Util::header_exists($res->[1], 'Content-Length');
     while (my ($k, $v) = splice(@{$res->[1]}, 0, 2)) {
         push @lines, "$k: $v\r\n";
         if (lc $k eq 'connection') {
@@ -124,8 +125,6 @@ sub handle_connection {
         }
     }
 
-    my $has_cl = Plack::Util::header_exists($res->[1], 'Content-Length');
-
     if ($req_count < $self->{max_keepalive_reqs} && $has_cl && ! defined($conn_value) && ($env->{HTTP_CONNECTION} || '') =~ /keep-alive/i) {
         unshift @lines, "Connection: keep-alive\r\n";
         $conn_value = "keep-alive";