diff --git a/add_to_pydotorg.py b/add_to_pydotorg.py
index 286f834a..8e88c292 100755
--- a/add_to_pydotorg.py
+++ b/add_to_pydotorg.py
@@ -266,7 +266,7 @@ def build_file_dict(
         "is_source": os_pk == 3,
         "url": download_root + f"{base_version(release)}/{rfile}",
         "md5_sum": md5sum_for(filename),
-        "sha256sum": sha256sum_for(filename),
+        "sha256_sum": sha256sum_for(filename),
         "filesize": filesize_for(filename),
         "download_button": add_download,
     }
diff --git a/tests/test_add_to_pydotorg.py b/tests/test_add_to_pydotorg.py
index aedac096..86f97de7 100644
--- a/tests/test_add_to_pydotorg.py
+++ b/tests/test_add_to_pydotorg.py
@@ -71,7 +71,7 @@ def test_build_file_dict(tmp_path: Path) -> None:
         "is_source": False,
         "url": f"{release_url}/test-artifact.txt",
         "md5_sum": "3e25960a79dbc69b674cd4ec67a72c62",
-        "sha256sum": "64ec88ca00b268e5ba1a35678a1b5316d212f4f366b2477232534a8aeca37f3c",
+        "sha256_sum": "64ec88ca00b268e5ba1a35678a1b5316d212f4f366b2477232534a8aeca37f3c",
         "filesize": 11,
         "download_button": True,
         "sigstore_bundle_file": f"{release_url}/test-artifact.txt.sigstore",