diff --git a/src/titiler/application/tests/routes/test_cog.py b/src/titiler/application/tests/routes/test_cog.py
index a7b1fb8d0..473967aab 100644
--- a/src/titiler/application/tests/routes/test_cog.py
+++ b/src/titiler/application/tests/routes/test_cog.py
@@ -443,3 +443,14 @@ def test_json_response_with_nan(rio, app):
     assert response.status_code == 200
     body = response.json()
     assert body["values"][0] is None
+
+
+@patch("rio_tiler.io.rasterio.rasterio")
+def test_invalid_format(rio, app):
+    """test /preview endpoint."""
+    rio.open = mock_rasterio_open
+
+    response = app.get(
+        "/cog/preview.png?url=https://myurl.com/cog.tif&bidx=1&bidx=1&bidx=1&bidx=1&rescale=0,1000&max_size=256"
+    )
+    assert response.status_code == 400
diff --git a/src/titiler/core/titiler/core/errors.py b/src/titiler/core/titiler/core/errors.py
index add40fd5e..3deafbfac 100644
--- a/src/titiler/core/titiler/core/errors.py
+++ b/src/titiler/core/titiler/core/errors.py
@@ -10,6 +10,7 @@
     InvalidBandName,
     InvalidColorFormat,
     InvalidExpression,
+    InvalidFormat,
     MissingAssets,
     MissingBands,
     RioTilerError,
@@ -48,6 +49,7 @@ class BadRequestError(TilerError):
     RioTilerError: status.HTTP_500_INTERNAL_SERVER_ERROR,
     Exception: status.HTTP_500_INTERNAL_SERVER_ERROR,
     InvalidExpression: status.HTTP_400_BAD_REQUEST,
+    InvalidFormat: status.HTTP_400_BAD_REQUEST,
 }