diff --git a/pyproject.toml b/pyproject.toml
index 23db412..592c5c9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -29,7 +29,7 @@ skyfield-data = ">=3,<6"
 python-dateutil = "^2.8"
 
 [tool.poetry.group.dev.dependencies]
-black = "^23.1"
+black = ">=23.1,<25.0"
 parameterized = "^0.9.0"
 coverage = "^6.1.2"
 coveralls = "^3.3.1"