diff --git a/packager/app/test/testdata/bear-320x240-vorbis-webm-golden.mpd b/packager/app/test/testdata/bear-320x240-vorbis-webm-golden.mpd
index 0cbd5ff024..355f828201 100644
--- a/packager/app/test/testdata/bear-320x240-vorbis-webm-golden.mpd
+++ b/packager/app/test/testdata/bear-320x240-vorbis-webm-golden.mpd
@@ -6,7 +6,7 @@
       <Representation id="0" bandwidth="69362" codecs="vorbis" mimeType="audio/webm" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <BaseURL>output_audio.webm</BaseURL>
-        <SegmentBase indexRange="23950-23999" timescale="1000000">
+        <SegmentBase indexRange="23950-23998" timescale="1000000">
           <Initialization range="0-4158"/>
         </SegmentBase>
       </Representation>
diff --git a/packager/app/test/testdata/bear-320x240-vp9-webm-golden.mpd b/packager/app/test/testdata/bear-320x240-vp9-webm-golden.mpd
index 59314d26fc..5fdc5afcb2 100644
--- a/packager/app/test/testdata/bear-320x240-vp9-webm-golden.mpd
+++ b/packager/app/test/testdata/bear-320x240-vp9-webm-golden.mpd
@@ -5,7 +5,7 @@
     <AdaptationSet id="0" contentType="video" width="320" height="240" frameRate="1000000/34000" par="16:9">
       <Representation id="0" bandwidth="203313" codecs="vp9" mimeType="video/webm" sar="427:320">
         <BaseURL>output_video.webm</BaseURL>
-        <SegmentBase indexRange="69485-69533" timescale="1000000">
+        <SegmentBase indexRange="69485-69532" timescale="1000000">
           <Initialization range="0-286"/>
         </SegmentBase>
       </Representation>
diff --git a/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd b/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd
index 0d4fd16daf..236818df44 100644
--- a/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd
+++ b/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd
@@ -8,7 +8,7 @@
           <cenc:pssh>AAAAMHBzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAABAxMjM0NTY3ODkwMTIzNDU2</cenc:pssh>
         </ContentProtection>
         <BaseURL>output_video.webm</BaseURL>
-        <SegmentBase indexRange="115225-115275" timescale="1000000">
+        <SegmentBase indexRange="115225-115274" timescale="1000000">
           <Initialization range="0-339"/>
         </SegmentBase>
       </Representation>
diff --git a/packager/app/test/testdata/bear-640x360-vp8-webm-golden.mpd b/packager/app/test/testdata/bear-640x360-vp8-webm-golden.mpd
index a4951cb6ea..205829a645 100644
--- a/packager/app/test/testdata/bear-640x360-vp8-webm-golden.mpd
+++ b/packager/app/test/testdata/bear-640x360-vp8-webm-golden.mpd
@@ -5,7 +5,7 @@
     <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="1000000/33000" par="16:9">
       <Representation id="0" bandwidth="335454" codecs="vp8" mimeType="video/webm" sar="1:1">
         <BaseURL>output_video.webm</BaseURL>
-        <SegmentBase indexRange="114676-114725" timescale="1000000">
+        <SegmentBase indexRange="114676-114724" timescale="1000000">
           <Initialization range="0-288"/>
         </SegmentBase>
       </Representation>
diff --git a/packager/media/formats/webm/single_segment_segmenter.cc b/packager/media/formats/webm/single_segment_segmenter.cc
index b8920b603b..5a8d64603f 100644
--- a/packager/media/formats/webm/single_segment_segmenter.cc
+++ b/packager/media/formats/webm/single_segment_segmenter.cc
@@ -80,7 +80,7 @@ bool SingleSegmentSegmenter::GetIndexRangeStartAndEnd(uint32_t* start,
   // The index is the Cues element, which is always placed at the end of the
   // file.
   *start = index_start_;
-  *end = writer_->file()->Size();
+  *end = writer_->file()->Size() - 1;
   return true;
 }