diff --git a/_examples/bar_chart/main.go b/_examples/bar_chart/main.go
index 693a300..ea15cee 100644
--- a/_examples/bar_chart/main.go
+++ b/_examples/bar_chart/main.go
@@ -19,6 +19,7 @@ func drawChart(res http.ResponseWriter, req *http.Request) {
 			},
 		},
 		Height:   512,
+		Width:    -1,
 		BarWidth: 60,
 		XAxis:    chart.StyleShow(),
 		YAxis: chart.YAxis{