diff --git a/src/GEval/Core.hs b/src/GEval/Core.hs
index 1569e2b..c6bd134 100644
--- a/src/GEval/Core.hs
+++ b/src/GEval/Core.hs
@@ -80,6 +80,7 @@ import GEval.CharMatch
 import GEval.BIO
 import GEval.ProbList
 import Data.Conduit.AutoDecompress
+import Text.Tokenizer
 
 import qualified Data.HashMap.Strict as M
 
@@ -213,7 +214,8 @@ data GEvalSpecification = GEvalSpecification
                             gesExpectedFile :: String,
                             gesInputFile :: String,
                             gesMetrics :: [Metric],
-                            gesPrecision :: Maybe Int}
+                            gesPrecision :: Maybe Int,
+                            gesTokenizer :: Maybe Tokenizer }
 
 gesMainMetric :: GEvalSpecification -> Metric
 gesMainMetric spec = case gesMetrics spec of
@@ -284,7 +286,8 @@ defaultGEvalSpecification = GEvalSpecification {
   gesExpectedFile = defaultExpectedFile,
   gesInputFile = defaultInputFile,
   gesMetrics = [defaultMetric],
-  gesPrecision = Nothing}
+  gesPrecision = Nothing,
+  gesTokenizer = Nothing}
 
 isEmptyFile :: FilePath -> IO (Bool)
 isEmptyFile path = do
diff --git a/src/GEval/OptionsParser.hs b/src/GEval/OptionsParser.hs
index 297234d..6193dbf 100644
--- a/src/GEval/OptionsParser.hs
+++ b/src/GEval/OptionsParser.hs
@@ -126,6 +126,11 @@ specParser = GEvalSpecification
     <> help "The name of the file with the input (applicable only for some metrics)" )
   <*> ((flip fromMaybe) <$> (singletonMaybe <$> altMetricReader) <*> metricReader)
   <*> optional precisionArgParser
+  <*> (optional $ option auto
+       ( long "tokenize"
+         <> short 'T'
+         <> metavar "TOKENIZER"
+         <> help "Tokenizer on expected and actual output before running evaluation (makes sense mostly for metrics such BLEU), only 13a tokenizer is implemented so far" ))
 
 singletonMaybe :: Maybe a -> Maybe [a]
 singletonMaybe (Just x) = Just [x]
diff --git a/src/Text/Tokenizer.hs b/src/Text/Tokenizer.hs
index 64d609c..ff8ebea 100644
--- a/src/Text/Tokenizer.hs
+++ b/src/Text/Tokenizer.hs
@@ -10,12 +10,21 @@ import Data.Monoid ((<>))
 import Text.Regex.PCRE.Heavy
 
 data Tokenizer = V13a
+  deriving (Eq)
+
+instance Show Tokenizer where
+  show V13a = "13a"
+
+instance Read Tokenizer where
+  readsPrec _ ('1':'3':'a':theRest) = [(V13a, theRest)]
 
 tokenize :: Maybe Tokenizer -> T.Text -> [T.Text]
-tokenize Nothing t = T.words t
-tokenize (Just V13a) t = T.words tWithSpaces
-  where tWithSpaces = T.strip tTokenized
-        tTokenized =
+tokenize mTokenizer = T.words . (tokenizeWithSpaces mTokenizer)
+
+tokenizeWithSpaces :: Maybe Tokenizer -> T.Text -> T.Text
+tokenizeWithSpaces Nothing t = t
+tokenizeWithSpaces (Just V13a) t = T.strip tTokenized
+  where tTokenized =
           gsub [re|([0-9])(-)|] (\(c:p:_) -> c <> space <> p)
           $ gsub [re|([\.,])([^0-9])|] (\(c:p:_) -> c <> space <> p)
           $ gsub [re|([^0-9])([\.,])|] (\(c:p:_) -> c <> space <> p)
diff --git a/test/Spec.hs b/test/Spec.hs
index 1270087..53f129a 100644
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -71,6 +71,8 @@ main = hspec $ do
       runGEvalTest "bleu-perfect" `shouldReturnAlmost` 1.0000
     it "empty translation" $
       runGEvalTest "bleu-empty" `shouldReturnAlmost` 0.0000
+    it "with tokenization" $
+      runGEvalTest "bleu-with-tokenization" `shouldReturnAlmost` 0.6501914150070065
   describe "Accuracy" $ do
     it "simple example" $
       runGEvalTest "accuracy-simple" `shouldReturnAlmost` 0.6
diff --git a/test/bleu-with-tokenization/bleu-with-tokenization-solution/test-A/out.tsv b/test/bleu-with-tokenization/bleu-with-tokenization-solution/test-A/out.tsv
new file mode 100644
index 0000000..28a7ed1
--- /dev/null
+++ b/test/bleu-with-tokenization/bleu-with-tokenization-solution/test-A/out.tsv
@@ -0,0 +1,3 @@
+Do you like pickles?
+John who is a plumber
+Alica has a cat.
diff --git a/test/bleu-with-tokenization/bleu-with-tokenization/config.txt b/test/bleu-with-tokenization/bleu-with-tokenization/config.txt
new file mode 100644
index 0000000..b615171
--- /dev/null
+++ b/test/bleu-with-tokenization/bleu-with-tokenization/config.txt
@@ -0,0 +1 @@
+--metric BLEU --tokenize 13a
diff --git a/test/bleu-with-tokenization/bleu-with-tokenization/test-A/expected.tsv b/test/bleu-with-tokenization/bleu-with-tokenization/test-A/expected.tsv
new file mode 100644
index 0000000..6a01ca8
--- /dev/null
+++ b/test/bleu-with-tokenization/bleu-with-tokenization/test-A/expected.tsv
@@ -0,0 +1,3 @@
+Do you like cucumbers?
+John, who is a plumber
+Alica has a cat.