diff --git a/tests/io_test.py b/tests/io_test.py
index b6989f60..88f0a3ae 100644
--- a/tests/io_test.py
+++ b/tests/io_test.py
@@ -98,11 +98,11 @@ def test_json_corr_io():
     for obs_list in [my_list, rw_list]:
         for tag in [None, "test"]:
             obs_list[3].tag = tag
-            for fp in [0, 2]:
-                for bp in [0, 7]:
-                    for corr_tag in [None, 'my_Corr_tag']:
+            for pad in [0, 2]:
+                for corr_tag in [None, 'my_Corr_tag']:
+                    for prange in [None, [3, 6]]:
                         for gap in [False, True]:
-                            my_corr = pe.Corr(obs_list, padding=[fp, bp])
+                            my_corr = pe.Corr(obs_list, padding=[pad, pad], prange=prange)
                             my_corr.tag = corr_tag
                             if gap:
                                 my_corr.content[4] = None
@@ -114,6 +114,7 @@ def test_json_corr_io():
                                 if entry is None:
                                     assert recover[index] is None
                             assert my_corr.tag == recover.tag
+                            assert my_corr.prange == recover.prange
                             assert my_corr.reweighted == recover.reweighted
 
 
@@ -123,13 +124,15 @@ def test_json_corr_2d_io():
     for tag in [None, "test"]:
         obs_list[3][0, 1].tag = tag
         for padding in [0, 1]:
-            my_corr = pe.Corr(obs_list, padding=[padding, padding])
-            my_corr.tag = tag
-            pe.input.json.dump_to_json(my_corr, 'corr')
-            recover = pe.input.json.load_json('corr')
-            os.remove('corr.json.gz')
-            assert np.all([np.all([o.is_zero() for o in q]) for q in [x.ravel() for x in (my_corr - recover) if x is not None]])
-            for index, entry in enumerate(my_corr):
-                if entry is None:
-                    assert recover[index] is None
-            assert my_corr.tag == recover.tag
+            for prange in [None, [3, 6]]:
+                my_corr = pe.Corr(obs_list, padding=[padding, padding], prange=prange)
+                my_corr.tag = tag
+                pe.input.json.dump_to_json(my_corr, 'corr')
+                recover = pe.input.json.load_json('corr')
+                os.remove('corr.json.gz')
+                assert np.all([np.all([o.is_zero() for o in q]) for q in [x.ravel() for x in (my_corr - recover) if x is not None]])
+                for index, entry in enumerate(my_corr):
+                    if entry is None:
+                        assert recover[index] is None
+                assert my_corr.tag == recover.tag
+                assert my_corr.prange == recover.prange