diff --git a/README.rst b/README.rst
index 6da05fe..3118f59 100644
--- a/README.rst
+++ b/README.rst
@@ -72,12 +72,12 @@ Usage
     $ speedtest-cli -h
     usage: speedtest-cli [-h] [--bytes] [--share] [--simple] [--list]
                          [--server SERVER] [--mini MINI] [--source SOURCE]
-                         [--version]
-    
+                         [--version] [--rrdfile RRDFILE]
+
     Command line interface for testing internet bandwidth using speedtest.net.
     --------------------------------------------------------------------------
     https://github.com/sivel/speedtest-cli
-    
+
     optional arguments:
       -h, --help       show this help message and exit
       --bytes          Display values in bytes instead of bits. Does not affect
@@ -90,6 +90,7 @@ Usage
       --mini MINI      URL of the Speedtest Mini server
       --source SOURCE  Source IP address to bind to
       --version        Show the version number and exit
+      --rrdfile        Output results to an RRD file, three columns, ping (ms), download (bits per second), and upload (bits per second)
 
 Inconsistency
 -------------
diff --git a/speedtest_cli.py b/speedtest_cli.py
index 105c390..10efa7c 100755
--- a/speedtest_cli.py
+++ b/speedtest_cli.py
@@ -486,6 +486,7 @@ def speedtest():
     parser.add_argument('--source', help='Source IP address to bind to')
     parser.add_argument('--version', action='store_true',
                         help='Show the version number and exit')
+    parser.add_argument('--rrdfile', help='Output results to an RRD file, three columns, ping (ms), download (bits per second), and upload (bits per second)')
 
     options = parser.parse_args()
     if isinstance(options, tuple):
@@ -634,6 +635,13 @@ def speedtest():
         print_()
     print_('Upload: %0.2f M%s/s' %
            ((ulspeed / 1000 / 1000) * args.units[1], args.units[0]))
+           
+    if args.rrdfile:
+    	import rrdtool
+    	rrdping = int(round(best['latency'], 0))
+    	rrdDLSpeedBits = int(round(dlspeed * 8, 0))
+    	rrdULSpeedBits = int(round(ulspeed * 8, 0))
+    	ret = rrdtool.update(args.rrdfile,'N:' + `rrdping` + ':' + `rrdDLSpeedBits` + ':' + `rrdULSpeedBits`);
 
     if args.share and args.mini:
         print_('Cannot generate a speedtest.net share results image while '