diff --git a/packages/node_modules/@node-red/nodes/core/network/21-httpin.js b/packages/node_modules/@node-red/nodes/core/network/21-httpin.js
index fc3fafd28..6cf243cf8 100644
--- a/packages/node_modules/@node-red/nodes/core/network/21-httpin.js
+++ b/packages/node_modules/@node-red/nodes/core/network/21-httpin.js
@@ -228,7 +228,7 @@ module.exports = function(RED) {
                             var diff = process.hrtime(startAt);
                             var ms = diff[0] * 1e3 + diff[1] * 1e-6;
                             var metricResponseTime = ms.toFixed(3);
-                            var metricContentLength = res._headers["content-length"];
+                            var metricContentLength = res.getHeader("content-length");
                             //assuming that _id has been set for res._metrics in HttpOut node!
                             node.metric("response.time.millis", {_msgid:res._msgid} , metricResponseTime);
                             node.metric("response.content-length.bytes", {_msgid:res._msgid} , metricContentLength);