diff --git a/requirements-dev.txt b/requirements-dev.txt
index 73e89bdc..454e0e06 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -17,3 +17,9 @@ wheel
 
 # Requirements for updating the vendored html5lib
 hashin
+
+# Requirements for format-check most recently black==20.8b1
+black; implementation_name == "cpython" and python_version > "3.5"
+
+# Requirements for type-check most recently mypy==0.790 and mypy-extensions==0.4.3
+mypy; implementation_name == "cpython" and python_version > "3.5"
diff --git a/tox.ini b/tox.ini
index 5eb57f44..dfd50982 100644
--- a/tox.ini
+++ b/tox.ini
@@ -61,7 +61,6 @@ basepython = python3.8
 changedir = scripts
 deps =
     -rrequirements-dev.txt
-    black
 commands =
     ./run_tests.sh format-check