diff --git a/src/main/java/org/takes/rs/RsWithBody.java b/src/main/java/org/takes/rs/RsWithBody.java
index 5180b6742..e4b186a8b 100644
--- a/src/main/java/org/takes/rs/RsWithBody.java
+++ b/src/main/java/org/takes/rs/RsWithBody.java
@@ -93,7 +93,7 @@ public RsWithBody(final Response res, final URL url) {
             new Response() {
                 @Override
                 public Iterable<String> head() throws IOException {
-                    return res.head();
+                    return append(res, url.openStream().available());
                 }
                 @Override
                 public InputStream body() throws IOException {
@@ -113,7 +113,7 @@ public RsWithBody(final Response res, final byte[] body) {
             new Response() {
                 @Override
                 public Iterable<String> head() throws IOException {
-                    return res.head();
+                    return append(res, body.length);
                 }
                 @Override
                 public InputStream body() {
@@ -133,7 +133,7 @@ public RsWithBody(final Response res, final InputStream body) {
             new Response() {
                 @Override
                 public Iterable<String> head() throws IOException {
-                    return res.head();
+                    return append(res, body.available());
                 }
                 @Override
                 public InputStream body() {
@@ -143,4 +143,18 @@ public InputStream body() {
         );
     }
 
+    /**
+     * Appends content length to header from response.
+     * @param res Response
+     * @param length Response body content length
+     * @return Iterable String of header attributes
+     * @throws IOException if something goes wrong.
+     */
+    private static Iterable<String> append(
+        final Response res, final int length) throws IOException {
+        return new RsWithHeader(
+            res, "Content-Length", Integer.toString(length)
+        ).head();
+    }
+
 }
diff --git a/src/test/java/org/takes/facets/fork/TkForkTest.java b/src/test/java/org/takes/facets/fork/TkForkTest.java
index 88b329f69..c87373c88 100644
--- a/src/test/java/org/takes/facets/fork/TkForkTest.java
+++ b/src/test/java/org/takes/facets/fork/TkForkTest.java
@@ -55,6 +55,7 @@ public void dispatchesByRegularExpression() throws IOException {
             Matchers.equalTo(
                 Joiner.on("\r\n").join(
                     "HTTP/1.1 200 OK",
+                    String.format("Content-Length: %s", body.length()),
                     "Content-Type: text/plain",
                     "",
                     body
diff --git a/src/test/java/org/takes/rs/RsTextTest.java b/src/test/java/org/takes/rs/RsTextTest.java
index 72d990e81..d7e03ab25 100644
--- a/src/test/java/org/takes/rs/RsTextTest.java
+++ b/src/test/java/org/takes/rs/RsTextTest.java
@@ -49,6 +49,7 @@ public void makesPlainTextResponse() throws IOException {
             Matchers.equalTo(
                 Joiner.on("\r\n").join(
                     "HTTP/1.1 200 OK",
+                    String.format("Content-Length: %s", body.length()),
                     "Content-Type: text/plain",
                     "",
                     body
diff --git a/src/test/java/org/takes/tk/TkHTMLTest.java b/src/test/java/org/takes/tk/TkHTMLTest.java
index 4773e8ee0..c47b5f0e5 100644
--- a/src/test/java/org/takes/tk/TkHTMLTest.java
+++ b/src/test/java/org/takes/tk/TkHTMLTest.java
@@ -52,6 +52,7 @@ public void createsTextResponse() throws IOException {
             Matchers.equalTo(
                 Joiner.on("\r\n").join(
                     "HTTP/1.1 200 OK",
+                    String.format("Content-Length: %s", body.length()),
                     "Content-Type: text/html",
                     "",
                     body
diff --git a/src/test/java/org/takes/tk/TkTextTest.java b/src/test/java/org/takes/tk/TkTextTest.java
index f22228220..6187e9de1 100644
--- a/src/test/java/org/takes/tk/TkTextTest.java
+++ b/src/test/java/org/takes/tk/TkTextTest.java
@@ -52,6 +52,7 @@ public void createsTextResponse() throws IOException {
             Matchers.equalTo(
                 Joiner.on("\r\n").join(
                     "HTTP/1.1 200 OK",
+                    String.format("Content-Length: %s", body.length()),
                     "Content-Type: text/plain",
                     "",
                     body