diff --git a/sqlite_utils/utils.py b/sqlite_utils/utils.py
index ee6695b55..542ee290c 100644
--- a/sqlite_utils/utils.py
+++ b/sqlite_utils/utils.py
@@ -577,6 +577,8 @@ def chunks(sequence: Iterable[T], size: int) -> Iterable[Iterable[T]]:
     :param sequence: Any Python iterator
     :param size: The size of each chunk
     """
+    if size < 1:
+        raise ValueError(f"chunk size must be at least 1, got {size}")
     iterator = iter(sequence)
     for item in iterator:
         yield itertools.chain([item], itertools.islice(iterator, size - 1))
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 360a4436a..2c608bddd 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -41,6 +41,16 @@ def test_chunks(size, expected):
     assert chunks == expected
 
 
+def test_chunks_size_zero_raises():
+    with pytest.raises(ValueError, match="chunk size must be at least 1"):
+        list(utils.chunks([1, 2, 3], 0))
+
+
+def test_chunks_negative_size_raises():
+    with pytest.raises(ValueError, match="chunk size must be at least 1"):
+        list(utils.chunks([1, 2, 3], -1))
+
+
 def test_hash_record():
     expected = "d383e7c0ba88f5ffcdd09be660de164b3847401a"
     assert utils.hash_record({"name": "Cleo", "twitter": "CleoPaws"}) == expected