diff --git a/docs/content/operations/metrics.md b/docs/content/operations/metrics.md
index a3964d4a102..2669208c175 100644
--- a/docs/content/operations/metrics.md
+++ b/docs/content/operations/metrics.md
@@ -29,8 +29,9 @@ Available Metrics
 |Metric|Description|Dimensions|Normal Value|
 |------|-----------|----------|------------|
 |`query/time`|Milliseconds taken to complete a query.|Common: dataSource, type, interval, hasFilters, duration, context, remoteAddress, id. Aggregation Queries: numMetrics, numComplexMetrics. GroupBy: numDimensions. TopN: threshold, dimension.|< 1s|
+|`query/bytes`|number of bytes returned in query response.|Common: dataSource, type, interval, hasFilters, duration, context, remoteAddress, id. Aggregation Queries: numMetrics, numComplexMetrics. GroupBy: numDimensions. TopN: threshold, dimension.| |
 |`query/node/time`|Milliseconds taken to query individual historical/realtime nodes.|id, status, server.|< 1s|
-|`query/node/bytes`|bytes returned from querying individual historical/realtime nodes.|id, status, server.| |
+|`query/node/bytes`|number of bytes returned from querying individual historical/realtime nodes.|id, status, server.| |
 |`query/node/ttfb`|Time to first byte. Milliseconds elapsed until broker starts receiving the response from individual historical/realtime nodes.|id, status, server.|< 1s|
 |`query/intervalChunk/time`|Only emitted if interval chunking is enabled. Milliseconds required to query an interval chunk.|id, status, chunkInterval (if interval chunking is enabled).|< 1s|
 
diff --git a/server/src/main/java/io/druid/server/QueryResource.java b/server/src/main/java/io/druid/server/QueryResource.java
index 7f0900a835e..0ebe1b52d51 100644
--- a/server/src/main/java/io/druid/server/QueryResource.java
+++ b/server/src/main/java/io/druid/server/QueryResource.java
@@ -25,6 +25,7 @@ import com.fasterxml.jackson.jaxrs.smile.SmileMediaTypes;
 import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.MapMaker;
+import com.google.common.io.CountingOutputStream;
 import com.google.inject.Inject;
 import com.metamx.common.guava.Sequence;
 import com.metamx.common.guava.Sequences;
@@ -184,15 +185,21 @@ public class QueryResource
                   public void write(OutputStream outputStream) throws IOException, WebApplicationException
                   {
                     // json serializer will always close the yielder
-                    jsonWriter.writeValue(outputStream, yielder);
-                    outputStream.flush(); // Some types of OutputStream suppress flush errors in the .close() method.
-                    outputStream.close();
+                    CountingOutputStream os = new CountingOutputStream(outputStream);
+                    jsonWriter.writeValue(os, yielder);
+
+                    os.flush(); // Some types of OutputStream suppress flush errors in the .close() method.
+                    os.close();
 
                     final long queryTime = System.currentTimeMillis() - start;
                     emitter.emit(
                         DruidMetrics.makeQueryTimeMetric(jsonMapper, theQuery, req.getRemoteAddr())
                                        .build("query/time", queryTime)
                     );
+                    emitter.emit(
+                        DruidMetrics.makeQueryTimeMetric(jsonMapper, theQuery, req.getRemoteAddr())
+                                    .build("query/bytes", os.getCount())
+                    );
 
                     requestLogger.log(
                         new RequestLogLine(
@@ -202,6 +209,7 @@ public class QueryResource
                             new QueryStats(
                                 ImmutableMap.<String, Object>of(
                                     "query/time", queryTime,
+                                    "query/bytes", os.getCount(),
                                     "success", true
                                 )
                             )