diff --git a/charts.factor b/charts.factor
index b6486f1816..b8054cd7b1 100644
--- a/charts.factor
+++ b/charts.factor
@@ -1,15 +1,19 @@
 ! Copyright (C) 2016-2017 Alexander Ilin.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: accessors kernel ui.gadgets ;
+USING: accessors arrays kernel sequences ui.gadgets ;
 IN: charts
 
-TUPLE: chart < gadget ;
+TUPLE: chart < gadget axes ;
 
 M: chart pref-dim* drop { 300 300 } ;
 
 ! Return the x and y ranges of the visible area.
 : chart-axes ( chart -- seq )
-    drop { { 0 300 } { 0 300 } } ;
+    [ dim>> ] [ axes>> ] bi [
+        nip
+    ] [
+        [ 0 swap 2array ] map
+    ] if* ;
 
 ! Return the { width height } of the visible area, in pixels.
 : chart-dim ( chart -- seq ) dim>> ;