diff --git a/scripts/generate_reports.py b/scripts/generate_reports.py
index cd9395b..ae7a3a7 100644
--- a/scripts/generate_reports.py
+++ b/scripts/generate_reports.py
@@ -175,7 +175,7 @@ def _generate_root_index() -> None:
     intervals = [
         p.name
         for p in OUTPUT_DIR.iterdir()
-        if p.is_dir() and p.name not in {"domains", "global"}
+        if p.is_dir() and p.name.lower() not in {"domains", "global"}
     ]
     intervals.sort()
 
diff --git a/tests/test_reports.py b/tests/test_reports.py
index 64fcc2d..fec898c 100644
--- a/tests/test_reports.py
+++ b/tests/test_reports.py
@@ -182,6 +182,8 @@ def test_generate_root_index(tmp_path, sample_reports, monkeypatch):
     # create dummy domain directories
     (tmp_path / "output" / "domains" / "foo.com").mkdir(parents=True)
     (tmp_path / "output" / "domains" / "bar.com").mkdir(parents=True)
+    # add an extra directory with capitalized name to ensure it's ignored
+    (tmp_path / "output" / "Global").mkdir(parents=True)
 
     gr._generate_root_index()
 
@@ -193,6 +195,7 @@ def test_generate_root_index(tmp_path, sample_reports, monkeypatch):
     assert '<option value="hourly">' in content
     assert '<option value="daily">' in content
     assert '<option value="global">' not in content
+    assert '<option value="Global">' not in content
 
     # check for domain options
     assert '<option value="foo.com">' in content