diff --git a/pyproject.toml b/pyproject.toml
index 5f36b0e..93641aa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,7 +26,6 @@ classifiers = [
 dependencies = [
     "numpy>=1.23.0,<2.0.0",
     "nibabel>=3.0.0",
-    "six>=1.10",
     "vtk"
 ]
 dynamic = ["version"]
diff --git a/tract_querier/tract_label_indices.py b/tract_querier/tract_label_indices.py
index f2d1f8a..d8bf8e7 100644
--- a/tract_querier/tract_label_indices.py
+++ b/tract_querier/tract_label_indices.py
@@ -1,11 +1,7 @@
 import warnings
 
-from six.moves import range
-
 import numpy as np
 
-from six.moves import range
-
 from .aabb import BoundingBox
 
 __all__ = ['TractographySpatialIndexing']
diff --git a/tract_querier/tract_math/decorator.py b/tract_querier/tract_math/decorator.py
index 3227999..ab89709 100644
--- a/tract_querier/tract_math/decorator.py
+++ b/tract_querier/tract_math/decorator.py
@@ -5,8 +5,6 @@
 import csv
 from os import path
 
-from six.moves import range
-
 import nibabel
 
 from ..tractography import (
diff --git a/tract_querier/tract_math/operations.py b/tract_querier/tract_math/operations.py
index 42a301a..3fa2de3 100644
--- a/tract_querier/tract_math/operations.py
+++ b/tract_querier/tract_math/operations.py
@@ -1,7 +1,5 @@
 from .decorator import tract_math_operation, set_dictionary_from_use_filenames_as_index
 
-from six.moves import range
-
 from warnings import warn
 
 import numpy
diff --git a/tract_querier/tractography/trackvis.py b/tract_querier/tractography/trackvis.py
index ca676d1..9398632 100644
--- a/tract_querier/tractography/trackvis.py
+++ b/tract_querier/tractography/trackvis.py
@@ -1,5 +1,4 @@
 from warnings import warn
-from six.moves import range
 
 import numpy
 
@@ -43,7 +42,7 @@ def tractography_to_trackvis_file(filename, tractography, affine=None, image_dim
     #data_new = {}
     # for k, v in data.iteritems():
     #    if (v[0].ndim > 1 and v[0].shape[1] > 1):
-    #        for i in xrange(v[0].shape[1]):
+    #        for i in range(v[0].shape[1]):
     #            data_new['%s_%02d' % (k, i)] = [
     #                v_[:, i] for v_ in v
     #            ]
diff --git a/tract_querier/tractography/tractography.py b/tract_querier/tractography/tractography.py
index 9861762..41a5f67 100644
--- a/tract_querier/tractography/tractography.py
+++ b/tract_querier/tractography/tractography.py
@@ -1,5 +1,4 @@
 import numpy as np
-from six.moves import range
 
 __all__ = ['Tractography']
 
diff --git a/tract_querier/tractography/vtkInterface.py b/tract_querier/tractography/vtkInterface.py
index 41f5b13..061ec0d 100644
--- a/tract_querier/tractography/vtkInterface.py
+++ b/tract_querier/tractography/vtkInterface.py
@@ -3,8 +3,6 @@
 from vtk.util import numpy_support as ns
 import numpy as np
 
-from six.moves import range
-
 from .tractography import Tractography
 from functools import reduce