diff --git a/pandas/core/indexers.py b/pandas/core/indexers.py
index 433bca940c028..209f889e809c3 100644
--- a/pandas/core/indexers.py
+++ b/pandas/core/indexers.py
@@ -144,9 +144,7 @@ def validate_indices(indices: np.ndarray, n: int) -> None:
     if len(indices):
         min_idx = indices.min()
         if min_idx < -1:
-            msg = "'indices' contains values less than allowed ({} < {})".format(
-                min_idx, -1
-            )
+            msg = f"'indices' contains values less than allowed ({min_idx} < -1)"
             raise ValueError(msg)
 
         max_idx = indices.max()