diff --git a/CHANGES.md b/CHANGES.md
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,7 @@
-# Version 0.1 (2016-12-???)
+# Version 0.2 (2016-12-14)
 
-  *
+  * ISO formatter
+
+# Version 0.1 (2016-12-13)
+
+  * ISO parser
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 
 # Welcome to Text Time library
 
-This library contains fast parser for ISO date from Text into UTCTime data
+This library contains fast parser and formatter for iso dates in Text.
 
 
 
diff --git a/src/Data/Text/Time.hs b/src/Data/Text/Time.hs
--- a/src/Data/Text/Time.hs
+++ b/src/Data/Text/Time.hs
@@ -2,10 +2,12 @@
 
 -- | Parser for ISO date from ByteString
 module Data.Text.Time
-    ( module Data.Text.Time.Parsers
+    ( module Data.Text.Time.Parse
+    , module Data.Text.Time.Format
     ) where
 
 
-import Data.Text.Time.Parsers
+import Data.Text.Time.Parse
+import Data.Text.Time.Format
 
 
diff --git a/src/Data/Text/Time/Format.hs b/src/Data/Text/Time/Format.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Text/Time/Format.hs
@@ -0,0 +1,15 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Data.Text.Time.Format
+    ( formatISODateTime
+    ) where
+
+import Data.Text.Lazy (Text)
+import Formatting (format, (%))
+import Formatting.Time (dateDash, hms)
+import Data.Time ( UTCTime )
+
+
+-- | Format ISO date.
+formatISODateTime :: UTCTime -> Text
+formatISODateTime utc = format (dateDash % "T" % hms) utc utc
diff --git a/src/Data/Text/Time/Parse.hs b/src/Data/Text/Time/Parse.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Text/Time/Parse.hs
@@ -0,0 +1,106 @@
+-- | This code is adapted from sqlite-simple package
+
+module Data.Text.Time.Parse
+    ( parseISODateTime
+    , parseUTCTimeOrError
+    ) where
+
+import           Control.Applicative
+import           Control.Monad (when)
+import qualified Data.Attoparsec.Text as A
+import           Data.Bits ((.&.))
+import           Data.Char (isDigit, ord)
+import qualified Data.Text as T
+import           Data.Time ( Day
+                           , TimeOfDay
+                           , UTCTime(..)
+                           , fromGregorian
+                           , fromGregorianValid
+                           , makeTimeOfDayValid
+                           , midnight
+                           , timeOfDayToTime
+                           )
+
+
+-- | Parse ISO date. If date can't be parsed then this function will return default value instead of error
+parseISODateTime :: T.Text -> UTCTime
+parseISODateTime str =
+    case parseUTCTimeOrError str of
+        Left _ -> defaultUTCTime
+        Right dt -> dt
+
+
+-- | Default time if date can't be parsed
+defaultUTCTime :: UTCTime
+defaultUTCTime = UTCTime (fromGregorian 1 1 1) 0
+
+
+parseUTCTimeOrError :: T.Text -> Either String UTCTime
+parseUTCTimeOrError = A.parseOnly getUTCTime
+
+-- | Create UTCTime parser for ISO date time
+-- This code is based on code from sqlite-simple package
+--
+getUTCTime :: A.Parser UTCTime
+getUTCTime = do
+    day  <- getDay
+    time <- ((A.char ' ' <|> A.char 'T') *> getTimeOfDay) <|> pure midnight
+    let time' = timeOfDayToTime time
+    return (UTCTime day time')
+
+
+-- | Date parser
+getDay :: A.Parser Day
+getDay = do
+    yearStr <- A.takeWhile isDigit
+    when (T.length yearStr < 4) (fail "year must consist of at least 4 digits")
+
+    let year = toNum yearStr
+    month <- (A.char '-' *> digits "month") <|> pure 1
+    day   <- (A.char '-' *> digits "day") <|> pure 1
+    case fromGregorianValid year month day of
+      Nothing -> fail "invalid date"
+      Just x  -> return $! x
+
+
+getTimeOfDay :: A.Parser TimeOfDay
+getTimeOfDay = do
+    hour   <- digits "hours"
+    _      <- A.char ':'
+    minute <- digits "minutes"
+    -- Allow omission of seconds.  If seconds is omitted, don't try to
+    -- parse the sub-second part.
+    (sec,subsec)
+           <- ((,) <$> (A.char ':' *> digits "seconds") <*> fract) <|> pure (0,0)
+
+    let picos' = sec + subsec
+
+    case makeTimeOfDayValid hour minute picos' of
+      Nothing -> fail "invalid time of day"
+      Just x  -> return $! x
+
+    where
+      fract =
+        (A.char '.' *> (decimal <$> A.takeWhile1 isDigit)) <|> pure 0
+
+
+toNum :: Num n => T.Text -> n
+toNum = T.foldl' (\a c -> 10*a + digit c) 0
+{-# INLINE toNum #-}
+
+digit :: Num n => Char -> n
+digit c = fromIntegral (ord c .&. 0x0f)
+{-# INLINE digit #-}
+
+digits :: Num n => String -> A.Parser n
+digits msg = do
+  x <- A.anyChar
+  y <- A.anyChar
+  if isDigit x && isDigit y
+  then return $! (10 * digit x + digit y)
+  else fail (msg ++ " is not 2 digits")
+{-# INLINE digits #-}
+
+decimal :: Fractional a => T.Text -> a
+decimal str = toNum str / 10^(T.length str)
+{-# INLINE decimal #-}
diff --git a/src/Data/Text/Time/Parsers.hs b/src/Data/Text/Time/Parsers.hs
deleted file mode 100644
--- a/src/Data/Text/Time/Parsers.hs
+++ /dev/null
@@ -1,107 +0,0 @@
-
-module Data.Text.Time.Parsers
-    ( parseISODateTime
-    , parseUTCTimeOrError
-    ) where
-
--- import Prelude
-import           Control.Applicative
-import           Control.Monad (when)
-import qualified Data.Attoparsec.Text as A
-import           Data.Bits ((.&.))
-import           Data.Char (isDigit, ord)
-import qualified Data.Text as T
-import           Data.Time ( Day
-                           , TimeOfDay
-                           , UTCTime(..)
-                           , fromGregorian
-                           , fromGregorianValid
-                           , makeTimeOfDayValid
-                           , midnight
-                           , timeOfDayToTime
-                           )
-
-
--- | Parse ISO date. If date can't be parsed then this function will return default value instead of error
--- Adapted from sqlite-simple package
-parseISODateTime :: T.Text -> UTCTime
-parseISODateTime str =
-    case parseUTCTimeOrError str of
-        Left _ -> defaultUTCTime
-        Right dt -> dt
-
-
--- | Default time if date can't be parsed
-defaultUTCTime :: UTCTime
-defaultUTCTime = UTCTime (fromGregorian 1 1 1) 0
-
-
-parseUTCTimeOrError :: T.Text -> Either String UTCTime
-parseUTCTimeOrError = A.parseOnly getUTCTime
-
--- | Create UTCTime parser for ISO date time
--- This code is based on code from sqlite-simple package
---
-getUTCTime :: A.Parser UTCTime
-getUTCTime = do
-    day  <- getDay
-    time <- ((A.char ' ' <|> A.char 'T') *> getTimeOfDay) <|> pure midnight
-    let time' = timeOfDayToTime time
-    return (UTCTime day time')
-
-
--- | Date parser
-getDay :: A.Parser Day
-getDay = do
-    yearStr <- A.takeWhile isDigit
-    when (T.length yearStr < 4) (fail "year must consist of at least 4 digits")
-
-    let year = toNum yearStr
-    month <- (A.char '-' *> digits "month") <|> pure 1
-    day   <- (A.char '-' *> digits "day") <|> pure 1
-    case fromGregorianValid year month day of
-      Nothing -> fail "invalid date"
-      Just x  -> return $! x
-
-
-getTimeOfDay :: A.Parser TimeOfDay
-getTimeOfDay = do
-    hour   <- digits "hours"
-    _      <- A.char ':'
-    minute <- digits "minutes"
-    -- Allow omission of seconds.  If seconds is omitted, don't try to
-    -- parse the sub-second part.
-    (sec,subsec)
-           <- ((,) <$> (A.char ':' *> digits "seconds") <*> fract) <|> pure (0,0)
-
-    let picos' = sec + subsec
-
-    case makeTimeOfDayValid hour minute picos' of
-      Nothing -> fail "invalid time of day"
-      Just x  -> return $! x
-
-    where
-      fract =
-        (A.char '.' *> (decimal <$> A.takeWhile1 isDigit)) <|> pure 0
-
-
-toNum :: Num n => T.Text -> n
-toNum = T.foldl' (\a c -> 10*a + digit c) 0
-{-# INLINE toNum #-}
-
-digit :: Num n => Char -> n
-digit c = fromIntegral (ord c .&. 0x0f)
-{-# INLINE digit #-}
-
-digits :: Num n => String -> A.Parser n
-digits msg = do
-  x <- A.anyChar
-  y <- A.anyChar
-  if isDigit x && isDigit y
-  then return $! (10 * digit x + digit y)
-  else fail (msg ++ " is not 2 digits")
-{-# INLINE digits #-}
-
-decimal :: Fractional a => T.Text -> a
-decimal str = toNum str / 10^(T.length str)
-{-# INLINE decimal #-}
diff --git a/test-src/Data/Text/TimeSpec.hs b/test-src/Data/Text/TimeSpec.hs
--- a/test-src/Data/Text/TimeSpec.hs
+++ b/test-src/Data/Text/TimeSpec.hs
@@ -9,7 +9,7 @@
 spec :: Spec
 spec = do
 
-  describe "Parsers" $ do
+  describe "Parse" $ do
 
     it "iso format: YYYY" $ do
         parseISODateTime "2014" `shouldBe` UTCTime (fromGregorian 2014 1 1) 0
@@ -27,3 +27,10 @@
     it "iso format: YYYY-MM-DD HH:MM:SS" $ do
         let t = timeOfDayToTime (TimeOfDay 12 34 56)
         parseISODateTime "2014-04-23 12:34:56" `shouldBe` UTCTime (fromGregorian 2014 4 23) t
+
+
+  describe "Format" $ do
+
+    it "to iso" $ do
+        formatISODateTime (UTCTime (fromGregorian 2014 1 1) 13513) `shouldBe` "2014-01-01T03:45:13"
+
diff --git a/text-time.cabal b/text-time.cabal
--- a/text-time.cabal
+++ b/text-time.cabal
@@ -1,5 +1,5 @@
 name:           text-time
-version:        0.1.0
+version:        0.2.0
 synopsis:       Library for Time parsing from Text into UTCTime
 License:        BSD3
 License-file:   LICENSE
@@ -9,7 +9,7 @@
                 LICENSE,
                 benchmark/*.hs
 description:
-    Fast parser for ISO date from Text to UTCTime
+    Fast parser and formatter for ISO date to and from Text
 homepage:       https://github.com/klangner/text-time
 author:         Krzysztof Langner
 maintainer:     klangner@gmail.com
@@ -28,12 +28,14 @@
   build-depends:
                     base >= 4.7 && < 5,
                     attoparsec < 0.14,
+                    formatting < 7,
                     text < 2,
                     time < 2
   exposed-modules:
                     Data.Text.Time
   other-modules:
-                    Data.Text.Time.Parsers
+                    Data.Text.Time.Parse
+                    Data.Text.Time.Format
 
 test-suite unit-tests
   type:             exitcode-stdio-1.0
@@ -45,9 +47,12 @@
                     QuickCheck >=2.6 && <3,
                     Cabal >=1.16.0 && <2,
                     attoparsec < 0.14,
+                    formatting < 7,
                     text < 2,
                     time < 2
   other-modules:
+                    Data.Text.Time.Parse
+                    Data.Text.Time.Format
                     Data.Text.Time,
                     Data.Text.TimeSpec
   hs-source-dirs: