diff --git a/tools/genfilter.py b/tools/genfilter.py
index 5ffab32..0c5f75a 100644
--- a/tools/genfilter.py
+++ b/tools/genfilter.py
@@ -84,24 +84,24 @@ class FilterGenerator(object):
 
     def generate(self):
         size = os.fstat(self.infile.fileno()).st_size
-        n = size / self.record_size
+        n = size // self.record_size
         m = int(math.ceil(-n*math.log10(ERROR_RATE) /
                           math.pow(math.log10(2), 2)))
-        m = (m/8 + 1)*8
+        m = (m//8 + 1)*8
         inmem = mmap.mmap(self.infile.fileno(),
                           size,
                           access=mmap.ACCESS_READ)
-        outmem = bytearray(m/8)
-        for i in xrange(0, n):
+        outmem = bytearray(m//8)
+        for i in range(0, n):
             offset = i*self.record_size
             b0, b1 = struct.unpack("=LL", inmem[offset:offset+8])
-            for k in xrange(0, 4):
+            for k in range(0, 4):
                 h = murmur_hash3_32(b0, b1, k)
                 h = int(h * (m / float(0xFFFFFFFF)))
-                outmem[h/8] |= (1 << (h%8))
+                outmem[h//8] |= (1 << (h%8))
         inmem.close()
-        # Convert bytearray to str, for Python 2.6 compatibility.
-        self.outfile.write(str(outmem))
+        # Convert bytearray to bytes, for Python 3 compatibility.
+        self.outfile.write(bytes(outmem))
 
 if __name__ == '__main__':
     import sys
@@ -110,7 +110,7 @@ if __name__ == '__main__':
     parser = argparse.ArgumentParser(description='filter')
     parser.add_argument('infile', type=argparse.FileType('r'),
                         help='input file')
-    parser.add_argument('outfile', type=argparse.FileType('w'),
+    parser.add_argument('outfile', type=argparse.FileType('wb'),
                         help='output file')
     parser.add_argument('record_size', type=int,
                         help='record size')
diff --git a/tools/sortlm.py b/tools/sortlm.py
index a0dd8fe..40f0837 100644
--- a/tools/sortlm.py
+++ b/tools/sortlm.py
@@ -40,10 +40,10 @@ class SortedGenerator(object):
         self.__min_cost = 0.0
 
     def read(self):
-        print "reading N-grams"
+        print("reading N-grams")
         self.__read_tries()
         self.__read_ngrams()
-        print "min cost = %lf" % self.__min_cost
+        print("min cost = %lf" % self.__min_cost)
 
     def __read_tries(self):
         while True:
@@ -58,7 +58,7 @@ class SortedGenerator(object):
             line = self.__infile.readline()
             if line == "":
                 break
-            line = line.strip()
+            line = line.strip('\n')
             if line == "":
                 break
             match = self.__ngram_line_regex.match(line)
@@ -89,7 +89,7 @@ class SortedGenerator(object):
                 line = self.__infile.readline()
                 if line == "":
                     break
-                line = line.strip()
+                line = line.strip('\n')
                 if line == "":
                     break
                 match = self.__ngram_line_regex.match(line)
@@ -125,14 +125,11 @@ class SortedGenerator(object):
         def quantize(cost, min_cost):
             return max(0, min(65535, int(cost * 65535 / min_cost)))
 
-        def cmp_header(a, b):
-            return cmp(a[0], b[0])
-
-        print "writing 1-gram file"
+        print("writing 1-gram file")
         unigram_offsets = {}
         unigram_file = open("%s.1gram" % self.__output_prefix, "wb")
         offset = 0
-        for ids, value in sorted(self.__ngram_entries[0].iteritems()):
+        for ids, value in sorted(self.__ngram_entries[0].items()):
             unigram_offsets[ids[0]] = offset
             s = struct.pack("=HHH",
                             quantize(value[0], self.__min_cost),
@@ -143,13 +140,13 @@ class SortedGenerator(object):
             offset += 1
         unigram_file.close()
 
-        print "writing 2-gram file"
+        print("writing 2-gram file")
         bigram_offsets = {}
         bigram_file = open("%s.2gram" % self.__output_prefix, "wb")
         keys = self.__ngram_entries[1].keys()
         items = [(struct.pack("=LL", ids[1], unigram_offsets[ids[0]]), ids) for ids in keys]
         offset = 0
-        for header, ids in sorted(items, cmp=cmp_header):
+        for header, ids in sorted(items, key=lambda x: x[0]):
             value = self.__ngram_entries[1][ids]
             bigram_offsets[ids] = offset
             s = struct.pack("=HH",
@@ -160,11 +157,11 @@ class SortedGenerator(object):
         bigram_file.close()
 
         if len(self.__ngram_entries[2]) > 0:
-            print "writing 3-gram file"
+            print("writing 3-gram file")
             trigram_file = open("%s.3gram" % self.__output_prefix, "wb")
             keys = self.__ngram_entries[2].keys()
             items = [(struct.pack("=LL", ids[2], bigram_offsets[(ids[0], ids[1])]), ids) for ids in keys]
-            for header, ids in sorted(items, cmp=cmp_header):
+            for header, ids in sorted(items, key=lambda x: x[0]):
                 value = self.__ngram_entries[2][ids]
                 s = struct.pack("=H",
                                 quantize(value[0], self.__min_cost))