diff --git a/docs/tuning.md b/docs/tuning.md
index 912c39879be8f..1c3bd0e8758ff 100644
--- a/docs/tuning.md
+++ b/docs/tuning.md
@@ -132,7 +132,7 @@ The best way to size the amount of memory consumption a dataset will require is
 into cache, and look at the "Storage" page in the web UI. The page will tell you how much memory the RDD
 is occupying.
 
-To estimate the memory consumption of a particular object, use `SizeEstimator`'s `estimate` method
+To estimate the memory consumption of a particular object, use `SizeEstimator`'s `estimate` method.
 This is useful for experimenting with different data layouts to trim memory usage, as well as
 determining the amount of space a broadcast variable will occupy on each executor heap.