diff --git a/Data/Default/Class.hs b/Data/Default/Class.hs
--- a/Data/Default/Class.hs
+++ b/Data/Default/Class.hs
@@ -39,9 +39,24 @@
 
 module Data.Default.Class (
 -- | This module defines a class for types with a default value.
+-- It also defines 'Default' instances for the types 'Int', 'Int8',
+-- 'Int16', 'Int32', 'Int64', 'Word', 'Word8', 'Word16', 'Word32', 'Word64',
+-- 'Integer', 'Float', 'Double', 'Ratio', 'Complex', 'CShort', 'CUShort',
+-- 'CInt', 'CUInt', 'CLong', 'CULong', 'CLLong', 'CULLong', 'CPtrdiff',
+-- 'CSize', 'CSigAtomic', 'CIntPtr', 'CUIntPtr', 'CIntMax', 'CUIntMax',
+-- 'CClock', 'CTime', 'CUSeconds', 'CSUSeconds', 'CFloat', 'CDouble', '(->)',
+-- 'IO', 'Maybe', '()', '[]', 'Ordering', 'Any', 'All', 'Last', 'First', 'Sum',
+-- 'Product', 'Endo', 'Dual', and tuples.
     Default(..)
 ) where
 
+import Data.Int
+import Data.Word
+import Data.Monoid
+import Data.Ratio
+import Data.Complex
+import Foreign.C.Types
+
 #if HAVE_GHC_GENERICS
 import GHC.Generics
 
@@ -70,3 +85,67 @@
     default def :: (Generic a, GDefault (Rep a)) => a
     def = to gdef
 #endif
+
+instance Default Int where def = 0
+instance Default Int8 where def = 0
+instance Default Int16 where def = 0
+instance Default Int32 where def = 0
+instance Default Int64 where def = 0
+instance Default Word where def = 0
+instance Default Word8 where def = 0
+instance Default Word16 where def = 0
+instance Default Word32 where def = 0
+instance Default Word64 where def = 0
+instance Default Integer where def = 0
+instance Default Float where def = 0
+instance Default Double where def = 0
+instance (Integral a) => Default (Ratio a) where def = 0
+instance (Default a, RealFloat a) => Default (Complex a) where def = def :+ def
+
+instance Default CShort     where def = 0
+instance Default CUShort    where def = 0
+instance Default CInt       where def = 0
+instance Default CUInt      where def = 0
+instance Default CLong      where def = 0
+instance Default CULong     where def = 0
+instance Default CLLong     where def = 0
+instance Default CULLong    where def = 0
+instance Default CPtrdiff   where def = 0
+instance Default CSize      where def = 0
+instance Default CSigAtomic where def = 0
+instance Default CIntPtr    where def = 0
+instance Default CUIntPtr   where def = 0
+instance Default CIntMax    where def = 0
+instance Default CUIntMax   where def = 0
+instance Default CClock     where def = 0
+instance Default CTime      where def = 0
+#if MIN_VERSION_base(4, 4, 0)
+instance Default CUSeconds  where def = 0
+instance Default CSUSeconds where def = 0
+#endif
+instance Default CFloat     where def = 0
+instance Default CDouble    where def = 0
+
+instance (Default r) => Default (e -> r) where def = const def
+instance (Default a) => Default (IO a) where def = return def
+
+instance Default (Maybe a) where def = Nothing
+
+instance Default () where def = mempty
+instance Default [a] where def = mempty
+instance Default Ordering where def = mempty
+instance Default Any where def = mempty
+instance Default All where def = mempty
+instance Default (Last a) where def = mempty
+instance Default (First a) where def = mempty
+instance (Num a) => Default (Sum a) where def = mempty
+instance (Num a) => Default (Product a) where def = mempty
+instance Default (Endo a) where def = mempty
+
+instance (Default a) => Default (Dual a) where def = Dual def
+instance (Default a, Default b) => Default (a, b) where def = (def, def)
+instance (Default a, Default b, Default c) => Default (a, b, c) where def = (def, def, def)
+instance (Default a, Default b, Default c, Default d) => Default (a, b, c, d) where def = (def, def, def, def)
+instance (Default a, Default b, Default c, Default d, Default e) => Default (a, b, c, d, e) where def = (def, def, def, def, def)
+instance (Default a, Default b, Default c, Default d, Default e, Default f) => Default (a, b, c, d, e, f) where def = (def, def, def, def, def, def)
+instance (Default a, Default b, Default c, Default d, Default e, Default f, Default g) => Default (a, b, c, d, e, f, g) where def = (def, def, def, def, def, def, def)
diff --git a/data-default-class.cabal b/data-default-class.cabal
--- a/data-default-class.cabal
+++ b/data-default-class.cabal
@@ -1,5 +1,5 @@
 Name:            data-default-class
-Version:         0.1.1
+Version:         0.1.2.0
 Cabal-Version:   >= 1.6
 Category:        Data
 Synopsis:        A class for types with a default value