diff --git a/CHANGES.md b/CHANGES.md
index c96d9a6e492..d3ba53fd05f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -27,6 +27,8 @@
 
 <!-- Changes to how Black can be configured -->
 
+- `.ipynb_checkpoints` directories are now excluded by default (#3293)
+
 ### Packaging
 
 <!-- Changes to how Black is packaged, such as dependency requirements -->
diff --git a/src/black/const.py b/src/black/const.py
index 03afc96e8d6..0e13f31517d 100644
--- a/src/black/const.py
+++ b/src/black/const.py
@@ -1,4 +1,4 @@
 DEFAULT_LINE_LENGTH = 88
-DEFAULT_EXCLUDES = r"/(\.direnv|\.eggs|\.git|\.hg|\.mypy_cache|\.nox|\.tox|\.venv|venv|\.svn|_build|buck-out|build|dist|__pypackages__)/"  # noqa: B950
+DEFAULT_EXCLUDES = r"/(\.direnv|\.eggs|\.git|\.hg|\.mypy_cache|\.nox|\.tox|\.venv|venv|\.svn|\.ipynb_checkpoints|_build|buck-out|build|dist|__pypackages__)/"  # noqa: B950
 DEFAULT_INCLUDES = r"(\.pyi?|\.ipynb)$"
 STDIN_PLACEHOLDER = "__BLACK_STDIN_FILENAME__"