diff --git a/biocommons/seqrepo/fastadir/fastadir.py b/biocommons/seqrepo/fastadir/fastadir.py
index <HASH>..<HASH> 100644
--- a/biocommons/seqrepo/fastadir/fastadir.py
+++ b/biocommons/seqrepo/fastadir/fastadir.py
@@ -88,7 +88,7 @@ class FastaDir(BaseReader, BaseWriter):
             yield recd
 
     def __len__(self):
-        return self.stats()["n_seqs"]
+        return self.stats()["n_sequences"]
 
     # ############################################################################
     # Public methods
diff --git a/tests/test_fastadir.py b/tests/test_fastadir.py
index <HASH>..<HASH> 100644
--- a/tests/test_fastadir.py
+++ b/tests/test_fastadir.py
@@ -23,6 +23,8 @@ def test_write_reread():
 
     assert "3" in fd
 
+    assert len(fd) == 3
+
     assert fd["3"] == "seq3", "test __getitem__ lookup"
 
     with pytest.raises(KeyError):
fixed KeyError in FastaDir.__len__ and added test