diff --git a/src/calibre/gui2/convert/__init__.py b/src/calibre/gui2/convert/__init__.py
index 0c3a8b5a4e..c1efe5b9af 100644
--- a/src/calibre/gui2/convert/__init__.py
+++ b/src/calibre/gui2/convert/__init__.py
@@ -10,7 +10,7 @@ import textwrap
 from functools import partial
 
 from PyQt4.Qt import QWidget, QSpinBox, QDoubleSpinBox, QLineEdit, QTextEdit, \
-    QCheckBox, QComboBox, Qt, QIcon, pyqtSignal
+    QCheckBox, QComboBox, Qt, QIcon, pyqtSignal, QLabel
 
 from calibre.customize.conversion import OptionRecommendation
 from calibre.ebooks.conversion.config import load_defaults, \
@@ -81,6 +81,21 @@ class Widget(QWidget):
         self.apply_recommendations(defaults)
         self.setup_help(get_help)
 
+        def process_child(child):
+            for g in child.children():
+                if isinstance(g, QLabel):
+                    buddy = g.buddy()
+                    if buddy is not None and hasattr(buddy, '_help'):
+                        g._help = buddy._help
+                        htext = unicode(buddy.toolTip()).strip()
+                        g.setToolTip(htext)
+                        g.setWhatsThis(htext)
+                        g.__class__.enterEvent = lambda obj, event: self.set_help(getattr(obj, '_help', obj.toolTip()))
+                else:
+                    process_child(g)
+        process_child(self)
+
+
     def restore_defaults(self, get_option):
         defaults = GuiRecommendations()
         defaults.merge_recommendations(get_option, OptionRecommendation.LOW,
diff --git a/src/calibre/gui2/preferences/main.py b/src/calibre/gui2/preferences/main.py
index fc01a33cf6..f7d49427c8 100644
--- a/src/calibre/gui2/preferences/main.py
+++ b/src/calibre/gui2/preferences/main.py
@@ -251,10 +251,28 @@ class Preferences(QMainWindow):
         self.close()
         self.run_wizard_requested.emit()
 
+    def set_tooltips_for_labels(self):
+
+        def process_child(child):
+            for g in child.children():
+                if isinstance(g, QLabel):
+                    buddy = g.buddy()
+                    if buddy is not None and hasattr(buddy, 'toolTip'):
+                        htext = unicode(buddy.toolTip()).strip()
+                        etext = unicode(g.toolTip()).strip()
+                        if htext and not etext:
+                            g.setToolTip(htext)
+                            g.setWhatsThis(htext)
+                else:
+                    process_child(g)
+
+        process_child(self.showing_widget)
+
     def show_plugin(self, plugin):
         self.showing_widget = plugin.create_widget(self.scroll_area)
         self.showing_widget.genesis(self.gui)
         self.showing_widget.initialize()
+        self.set_tooltips_for_labels()
         self.scroll_area.setWidget(self.showing_widget)
         self.stack.setCurrentIndex(1)
         self.showing_widget.show()