diff --git a/docs/source/contributing/contributing.md b/docs/source/contributing/contributing.md
index 1bc38618..3e333ab6 100644
--- a/docs/source/contributing/contributing.md
+++ b/docs/source/contributing/contributing.md
@@ -64,8 +64,8 @@ Read the [next section](#guidelines-to-getting-a-pull-request-merged) for guidel
 6. Wait for a community member to merge your changes.
   Remember that **someone else must merge your pull request**.
   That goes for new contributors and long term maintainers alike.
-  Because `master` is continuously deployed to mybinder.org it is essential
-  that `master` is always in a deployable state.
+  Because `main` is continuously deployed to mybinder.org it is essential
+  that `main` is always in a deployable state.
 7. (optional) Deploy a new version of repo2docker to mybinder.org by [following these steps](http://mybinder-sre.readthedocs.io/en/latest/deployment/how.html)
 
 ## Guidelines to getting a Pull Request merged
diff --git a/docs/source/contributing/roadmap.md b/docs/source/contributing/roadmap.md
index c2e9a146..0a620cad 100644
--- a/docs/source/contributing/roadmap.md
+++ b/docs/source/contributing/roadmap.md
@@ -60,7 +60,7 @@ creating the environment in which a piece of software can be executed.
 
 The "Now" items are being actively worked on by the project:
 * reduce documentation typos and syntax errors
-* increase test coverage to 80% (see https://codecov.io/gh/jupyterhub/repo2docker/tree/master/repo2docker for low coverage files)
+* increase test coverage to 80% (see https://codecov.io/gh/jupyterhub/repo2docker/tree/main/repo2docker for low coverage files)
 * mounting repository contents in locations that is not `/home/jovyan`
 * investigate options for pinning repo2docker versions ([#490](https://github.com/jupyterhub/repo2docker/issues/490))
 
diff --git a/docs/source/contributing/tasks.md b/docs/source/contributing/tasks.md
index 49bb970f..62d58f38 100644
--- a/docs/source/contributing/tasks.md
+++ b/docs/source/contributing/tasks.md
@@ -115,7 +115,7 @@ test to prevent the bug from coming back/the feature breaking in the future.
 
 ## Creating a Release
 
-We make a release of whatever is on `master` every month. We use "calendar versioning".
+We make a release of whatever is on `main` every month. We use "calendar versioning".
 Monthly releases give users a predictable pattern for when releases are going to
 happen and prevents locking up improvements for fixes for long periods of time.
 
@@ -135,7 +135,7 @@ V=YYYY.MM.0; git tag -am "release $V" $V
 > If you need to make a second (or third) release in a month increment the
 > trailing 0 of the version to 1 (or 2).
 
-Then push this change up to the master repository
+Then push this change up to the main repository
 
 ```
 git push origin --tags
diff --git a/docs/source/howto/user_interface.rst b/docs/source/howto/user_interface.rst
index b79c1ba6..be196e6c 100644
--- a/docs/source/howto/user_interface.rst
+++ b/docs/source/howto/user_interface.rst
@@ -30,7 +30,7 @@ For example, the following Binder URL will open the
 `pyTudes repository <https://github.com/norvig/pytudes>`_
 and begin a JupyterLab session in the ``ipynb`` folder:
 
-https://mybinder.org/v2/gh/norvig/pytudes/master?urlpath=lab/tree/ipynb
+https://mybinder.org/v2/gh/norvig/pytudes/HEAD?urlpath=lab/tree/ipynb
 
 The ``/tree/ipynb`` above is how JupyterLab directs you to a specific file
 or folder.
@@ -61,7 +61,7 @@ For example, the following Binder URL will open the
 `pyTudes repository <https://github.com/norvig/pytudes>`_
 and begin an nteract session in the ``ipynb`` folder:
 
-https://mybinder.org/v2/gh/norvig/pytudes/master?urlpath=nteract/tree/ipynb
+https://mybinder.org/v2/gh/norvig/pytudes/HEAD?urlpath=nteract/tree/ipynb
 
 The ``/tree/ipynb`` above is how nteract directs you to a specific file
 or folder.
@@ -83,7 +83,7 @@ RStudio will be accessible by appending ``/rstudio`` to the URL, like so:
 For example, the following Binder link will open an RStudio session in
 the `R demo repository <https://github.com/binder-examples/r>`_.
 
-http://mybinder.org/v2/gh/binder-examples/r/master?urlpath=rstudio
+http://mybinder.org/v2/gh/binder-examples/r/HEAD?urlpath=rstudio
 
 
 Shiny
@@ -106,7 +106,7 @@ a Shiny app.
 For example, the following Binder link will open a Shiny session in
 the `R demo repository <https://github.com/binder-examples/r>`_.
 
-http://mybinder.org/v2/gh/binder-examples/r/master?urlpath=shiny/bus-dashboard/
+http://mybinder.org/v2/gh/binder-examples/r/HEAD?urlpath=shiny/bus-dashboard/
 
 
 Stencila
diff --git a/docs/source/install.rst b/docs/source/install.rst
index e8fea2c9..be9c91b2 100644
--- a/docs/source/install.rst
+++ b/docs/source/install.rst
@@ -48,7 +48,7 @@ We recommend installing ``repo2docker`` with the ``pip`` tool::
 
 for the latest release. To install the most recent code from the upstream repository, run::
 
-    python3 -m pip install https://github.com/jupyterhub/repo2docker/archive/master.zip
+    python3 -m pip install https://github.com/jupyterhub/repo2docker/archive/main.zip
 
 For information on using ``repo2docker``, see :ref:`usage`.
 
diff --git a/hooks/post_push b/hooks/post_push
index a2b89246..d03f1c6b 100644
--- a/hooks/post_push
+++ b/hooks/post_push
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-# when building jupyter/repo2docker:master
+# when building jupyter/repo2docker:main
 # also push jupyter/repo2docker:1.2.3-3.abcd1234 (replace + with -)
 version=$(docker run $DOCKER_REPO:$DOCKER_TAG jupyter-repo2docker --version | sed s@+@-@)
 VERSION_IMAGE="$DOCKER_REPO:$version"