diff --git a/.gitignore b/.gitignore
index 07a1cf3..f6e9528 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 db.sqlite3
 dist
 .coverage
+docs/build
diff --git a/checkcert/checkcert.py b/checkcert/checkcert.py
index 2a5d04d..859c584 100644
--- a/checkcert/checkcert.py
+++ b/checkcert/checkcert.py
@@ -115,8 +115,12 @@ def get_host_list_tuple(hosts: list) -> List[Tuple[str, int]]:
     is_flag=True,
     help="Output only the SAN names to use in passing to certbot for example",
 )
+@click.option(
+    "--pre/--no-pre", default=False, help="prefix the --san-only with the separator"
+)
+@click.option("--sep", "-s", default=" ", help="Separator to use in --san-only output")
 @click.argument("hosts", nargs=-1)
-def main(san, dump, color, filename, valid, san_only, hosts):
+def main(san, dump, color, filename, valid, san_only, sep, pre, hosts):
     """Return information about certificates given including their validity"""
     # setup the list of tuples
     # handle a domain given with a : in it to specify the port
@@ -134,8 +138,14 @@ def main(san, dump, color, filename, valid, san_only, hosts):
                 print(get_x509_text(hostinfo.cert).decode())
             else:
                 if san_only:
-                    san_names = " ".join(get_alt_names(hostinfo.cert))
-                    print(san_names)
+                    output_string = ""
+                    if pre:
+                        output_string += f"{sep}".lstrip()
+                    alt_names = get_alt_names(hostinfo.cert)
+                    if hostinfo.hostname not in alt_names:
+                        alt_names.insert(0, hostinfo.hostname)
+                    output_string += f"{sep}".join(alt_names)
+                    print(output_string)
                     break
                 output_string += (
                     f"{hostinfo.hostname} "
diff --git a/docs/Makefile b/docs/Makefile
new file mode 100644
index 0000000..d0c3cbf
--- /dev/null
+++ b/docs/Makefile
@@ -0,0 +1,20 @@
+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line, and also
+# from the environment for the first two.
+SPHINXOPTS    ?=
+SPHINXBUILD   ?= sphinx-build
+SOURCEDIR     = source
+BUILDDIR      = build
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
diff --git a/docs/source/conf.py b/docs/source/conf.py
new file mode 100644
index 0000000..78b9057
--- /dev/null
+++ b/docs/source/conf.py
@@ -0,0 +1,55 @@
+# Configuration file for the Sphinx documentation builder.
+#
+# This file only contains a selection of the most common options. For a full
+# list see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+
+# -- Path setup --------------------------------------------------------------
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#
+# import os
+# import sys
+# sys.path.insert(0, os.path.abspath('.'))
+
+
+# -- Project information -----------------------------------------------------
+
+project = 'checkcert'
+copyright = '2021, Alex Kelly'
+author = 'Alex Kelly'
+
+# The full version, including alpha/beta/rc tags
+release = '0.5.0'
+
+
+# -- General configuration ---------------------------------------------------
+
+# Add any Sphinx extension module names here, as strings. They can be
+# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
+# ones.
+extensions = [
+]
+
+# Add any paths that contain templates here, relative to this directory.
+templates_path = ['_templates']
+
+# List of patterns, relative to source directory, that match files and
+# directories to ignore when looking for source files.
+# This pattern also affects html_static_path and html_extra_path.
+exclude_patterns = []
+
+
+# -- Options for HTML output -------------------------------------------------
+
+# The theme to use for HTML and HTML Help pages.  See the documentation for
+# a list of builtin themes.
+#
+html_theme = 'alabaster'
+
+# Add any paths that contain custom static files (such as style sheets) here,
+# relative to this directory. They are copied after the builtin static files,
+# so a file named "default.css" will overwrite the builtin "default.css".
+html_static_path = ['_static']
\ No newline at end of file
diff --git a/docs/source/index.rst b/docs/source/index.rst
new file mode 100644
index 0000000..da81419
--- /dev/null
+++ b/docs/source/index.rst
@@ -0,0 +1,22 @@
+.. checkcert documentation master file, created by
+   sphinx-quickstart on Mon Oct  4 12:00:40 2021.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+Welcome to checkcert's documentation!
+=====================================
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Contents:
+
+   introduction
+
+
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`
diff --git a/poetry.lock b/poetry.lock
index ba56da6..97f9ace 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1,3 +1,11 @@
+[[package]]
+name = "alabaster"
+version = "0.7.12"
+description = "A configurable sidebar-enabled Sphinx theme"
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "astroid"
 version = "2.8.0"
@@ -33,6 +41,17 @@ docs = ["furo", "sphinx", "zope.interface", "sphinx-notfound-page"]
 tests = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "mypy", "pytest-mypy-plugins", "zope.interface"]
 tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "mypy", "pytest-mypy-plugins"]
 
+[[package]]
+name = "babel"
+version = "2.9.1"
+description = "Internationalization utilities"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+
+[package.dependencies]
+pytz = ">=2015.7"
+
 [[package]]
 name = "bleach"
 version = "4.1.0"
@@ -186,6 +205,14 @@ category = "dev"
 optional = false
 python-versions = ">=3.5"
 
+[[package]]
+name = "imagesize"
+version = "1.2.0"
+description = "Getting image size from png/jpeg/jpeg2000/gif file"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+
 [[package]]
 name = "importlib-metadata"
 version = "4.8.1"
@@ -244,6 +271,20 @@ python-versions = ">=3.6"
 test = ["pytest", "pytest-trio", "pytest-asyncio", "testpath", "trio", "async-timeout"]
 trio = ["trio", "async-generator"]
 
+[[package]]
+name = "jinja2"
+version = "3.0.1"
+description = "A very fast and expressive template engine."
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.dependencies]
+MarkupSafe = ">=2.0"
+
+[package.extras]
+i18n = ["Babel (>=2.7)"]
+
 [[package]]
 name = "keyring"
 version = "23.2.1"
@@ -270,6 +311,14 @@ category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*"
 
+[[package]]
+name = "markupsafe"
+version = "2.0.1"
+description = "Safely add untrusted strings to HTML/XML markup."
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
 [[package]]
 name = "mccabe"
 version = "0.6.1"
@@ -460,6 +509,14 @@ docs = ["Sphinx (==1.3.6)"]
 mypy = ["mypy", "types-requests"]
 test = ["coverage (>=5,<6)", "pytest (>=5,<6)", "pytest-xdist (>=1,<2)", "pytest-mock (>=2,<3)", "responses (==0.13.3)", "mock (==1.3.0)"]
 
+[[package]]
+name = "pytz"
+version = "2021.3"
+description = "World timezone definitions, modern and historical"
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "pywin32-ctypes"
 version = "0.2.0"
@@ -576,6 +633,116 @@ category = "dev"
 optional = false
 python-versions = ">=3.5"
 
+[[package]]
+name = "snowballstemmer"
+version = "2.1.0"
+description = "This package provides 29 stemmers for 28 languages generated from Snowball algorithms."
+category = "dev"
+optional = false
+python-versions = "*"
+
+[[package]]
+name = "sphinx"
+version = "4.2.0"
+description = "Python documentation generator"
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.dependencies]
+alabaster = ">=0.7,<0.8"
+babel = ">=1.3"
+colorama = {version = ">=0.3.5", markers = "sys_platform == \"win32\""}
+docutils = ">=0.14,<0.18"
+imagesize = "*"
+Jinja2 = ">=2.3"
+packaging = "*"
+Pygments = ">=2.0"
+requests = ">=2.5.0"
+snowballstemmer = ">=1.1"
+sphinxcontrib-applehelp = "*"
+sphinxcontrib-devhelp = "*"
+sphinxcontrib-htmlhelp = ">=2.0.0"
+sphinxcontrib-jsmath = "*"
+sphinxcontrib-qthelp = "*"
+sphinxcontrib-serializinghtml = ">=1.1.5"
+
+[package.extras]
+docs = ["sphinxcontrib-websupport"]
+lint = ["flake8 (>=3.5.0)", "isort", "mypy (>=0.900)", "docutils-stubs", "types-typed-ast", "types-pkg-resources", "types-requests"]
+test = ["pytest", "pytest-cov", "html5lib", "cython", "typed-ast"]
+
+[[package]]
+name = "sphinxcontrib-applehelp"
+version = "1.0.2"
+description = "sphinxcontrib-applehelp is a sphinx extension which outputs Apple help books"
+category = "dev"
+optional = false
+python-versions = ">=3.5"
+
+[package.extras]
+lint = ["flake8", "mypy", "docutils-stubs"]
+test = ["pytest"]
+
+[[package]]
+name = "sphinxcontrib-devhelp"
+version = "1.0.2"
+description = "sphinxcontrib-devhelp is a sphinx extension which outputs Devhelp document."
+category = "dev"
+optional = false
+python-versions = ">=3.5"
+
+[package.extras]
+lint = ["flake8", "mypy", "docutils-stubs"]
+test = ["pytest"]
+
+[[package]]
+name = "sphinxcontrib-htmlhelp"
+version = "2.0.0"
+description = "sphinxcontrib-htmlhelp is a sphinx extension which renders HTML help files"
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.extras]
+lint = ["flake8", "mypy", "docutils-stubs"]
+test = ["pytest", "html5lib"]
+
+[[package]]
+name = "sphinxcontrib-jsmath"
+version = "1.0.1"
+description = "A sphinx extension which renders display math in HTML via JavaScript"
+category = "dev"
+optional = false
+python-versions = ">=3.5"
+
+[package.extras]
+test = ["pytest", "flake8", "mypy"]
+
+[[package]]
+name = "sphinxcontrib-qthelp"
+version = "1.0.3"
+description = "sphinxcontrib-qthelp is a sphinx extension which outputs QtHelp document."
+category = "dev"
+optional = false
+python-versions = ">=3.5"
+
+[package.extras]
+lint = ["flake8", "mypy", "docutils-stubs"]
+test = ["pytest"]
+
+[[package]]
+name = "sphinxcontrib-serializinghtml"
+version = "1.1.5"
+description = "sphinxcontrib-serializinghtml is a sphinx extension which outputs \"serialized\" HTML files (json and pickle)."
+category = "dev"
+optional = false
+python-versions = ">=3.5"
+
+[package.extras]
+lint = ["flake8", "mypy", "docutils-stubs"]
+test = ["pytest"]
+
 [[package]]
 name = "toml"
 version = "0.10.2"
@@ -687,9 +854,13 @@ testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytes
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.9"
-content-hash = "f9e3c5502f1aa3c91b8c2a76f7f4c14d39cb84281143d987cf9e8ed043efa175"
+content-hash = "83eb072728504c8b6d08f07db01396bd7bccd29fa73a938e36be0e0f12495bca"
 
 [metadata.files]
+alabaster = [
+    {file = "alabaster-0.7.12-py2.py3-none-any.whl", hash = "sha256:446438bdcca0e05bd45ea2de1668c1d9b032e1a9154c2c259092d77031ddd359"},
+    {file = "alabaster-0.7.12.tar.gz", hash = "sha256:a661d72d58e6ea8a57f7a86e37d86716863ee5e92788398526d58b26a4e4dc02"},
+]
 astroid = [
     {file = "astroid-2.8.0-py3-none-any.whl", hash = "sha256:dcc06f6165f415220013801642bd6c9808a02967070919c4b746c6864c205471"},
     {file = "astroid-2.8.0.tar.gz", hash = "sha256:fe81f80c0b35264acb5653302ffbd935d394f1775c5e4487df745bf9c2442708"},
@@ -702,6 +873,10 @@ attrs = [
     {file = "attrs-21.2.0-py2.py3-none-any.whl", hash = "sha256:149e90d6d8ac20db7a955ad60cf0e6881a3f20d37096140088356da6c716b0b1"},
     {file = "attrs-21.2.0.tar.gz", hash = "sha256:ef6aaac3ca6cd92904cdd0d83f629a15f18053ec84e6432106f7a4d04ae4f5fb"},
 ]
+babel = [
+    {file = "Babel-2.9.1-py2.py3-none-any.whl", hash = "sha256:ab49e12b91d937cd11f0b67cb259a57ab4ad2b59ac7a3b41d6c06c0ac5b0def9"},
+    {file = "Babel-2.9.1.tar.gz", hash = "sha256:bc0c176f9f6a994582230df350aa6e05ba2ebe4b3ac317eab29d9be5d2768da0"},
+]
 bleach = [
     {file = "bleach-4.1.0-py2.py3-none-any.whl", hash = "sha256:4d2651ab93271d1129ac9cbc679f524565cc8a1b791909c4a51eac4446a15994"},
     {file = "bleach-4.1.0.tar.gz", hash = "sha256:0900d8b37eba61a802ee40ac0061f8c2b5dee29c1927dd1d233e075ebf5a71da"},
@@ -865,6 +1040,10 @@ idna = [
     {file = "idna-3.2-py3-none-any.whl", hash = "sha256:14475042e284991034cb48e06f6851428fb14c4dc953acd9be9a5e95c7b6dd7a"},
     {file = "idna-3.2.tar.gz", hash = "sha256:467fbad99067910785144ce333826c71fb0e63a425657295239737f7ecd125f3"},
 ]
+imagesize = [
+    {file = "imagesize-1.2.0-py2.py3-none-any.whl", hash = "sha256:6965f19a6a2039c7d48bca7dba2473069ff854c36ae6f19d2cde309d998228a1"},
+    {file = "imagesize-1.2.0.tar.gz", hash = "sha256:b1f6b5a4eab1f73479a50fb79fcf729514a900c341d8503d62a62dbc4127a2b1"},
+]
 importlib-metadata = [
     {file = "importlib_metadata-4.8.1-py3-none-any.whl", hash = "sha256:b618b6d2d5ffa2f16add5697cf57a46c76a56229b0ed1c438322e4e95645bd15"},
     {file = "importlib_metadata-4.8.1.tar.gz", hash = "sha256:f284b3e11256ad1e5d03ab86bb2ccd6f5339688ff17a4d797a0fe7df326f23b1"},
@@ -886,6 +1065,10 @@ jeepney = [
     {file = "jeepney-0.7.1-py3-none-any.whl", hash = "sha256:1b5a0ea5c0e7b166b2f5895b91a08c14de8915afda4407fb5022a195224958ac"},
     {file = "jeepney-0.7.1.tar.gz", hash = "sha256:fa9e232dfa0c498bd0b8a3a73b8d8a31978304dcef0515adc859d4e096f96f4f"},
 ]
+jinja2 = [
+    {file = "Jinja2-3.0.1-py3-none-any.whl", hash = "sha256:1f06f2da51e7b56b8f238affdd6b4e2c61e39598a378cc49345bc1bd42a978a4"},
+    {file = "Jinja2-3.0.1.tar.gz", hash = "sha256:703f484b47a6af502e743c9122595cc812b0271f661722403114f71a79d0f5a4"},
+]
 keyring = [
     {file = "keyring-23.2.1-py3-none-any.whl", hash = "sha256:bd2145a237ed70c8ce72978b497619ddfcae640b6dcf494402d5143e37755c6e"},
     {file = "keyring-23.2.1.tar.gz", hash = "sha256:6334aee6073db2fb1f30892697b1730105b5e9a77ce7e61fca6b435225493efe"},
@@ -914,6 +1097,42 @@ lazy-object-proxy = [
     {file = "lazy_object_proxy-1.6.0-cp39-cp39-win32.whl", hash = "sha256:1fee665d2638491f4d6e55bd483e15ef21f6c8c2095f235fef72601021e64f61"},
     {file = "lazy_object_proxy-1.6.0-cp39-cp39-win_amd64.whl", hash = "sha256:f5144c75445ae3ca2057faac03fda5a902eff196702b0a24daf1d6ce0650514b"},
 ]
+markupsafe = [
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:f9081981fe268bd86831e5c75f7de206ef275defcb82bc70740ae6dc507aee51"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:0955295dd5eec6cb6cc2fe1698f4c6d84af2e92de33fbcac4111913cd100a6ff"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-manylinux1_x86_64.whl", hash = "sha256:0446679737af14f45767963a1a9ef7620189912317d095f2d9ffa183a4d25d2b"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-manylinux2010_i686.whl", hash = "sha256:f826e31d18b516f653fe296d967d700fddad5901ae07c622bb3705955e1faa94"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-manylinux2010_x86_64.whl", hash = "sha256:fa130dd50c57d53368c9d59395cb5526eda596d3ffe36666cd81a44d56e48872"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-manylinux2014_aarch64.whl", hash = "sha256:905fec760bd2fa1388bb5b489ee8ee5f7291d692638ea5f67982d968366bef9f"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-win32.whl", hash = "sha256:6c4ca60fa24e85fe25b912b01e62cb969d69a23a5d5867682dd3e80b5b02581d"},
+    {file = "MarkupSafe-2.0.1-cp36-cp36m-win_amd64.whl", hash = "sha256:b2f4bf27480f5e5e8ce285a8c8fd176c0b03e93dcc6646477d4630e83440c6a9"},
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+    {file = "MarkupSafe-2.0.1-cp37-cp37m-win_amd64.whl", hash = "sha256:611d1ad9a4288cf3e3c16014564df047fe08410e628f89805e475368bd304914"},
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+    {file = "MarkupSafe-2.0.1-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:97383d78eb34da7e1fa37dd273c20ad4320929af65d156e35a5e2d89566d9dfb"},
+    {file = "MarkupSafe-2.0.1-cp38-cp38-win32.whl", hash = "sha256:023cb26ec21ece8dc3907c0e8320058b2e0cb3c55cf9564da612bc325bed5e64"},
+    {file = "MarkupSafe-2.0.1-cp38-cp38-win_amd64.whl", hash = "sha256:984d76483eb32f1bcb536dc27e4ad56bba4baa70be32fa87152832cdd9db0833"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-macosx_10_9_universal2.whl", hash = "sha256:2ef54abee730b502252bcdf31b10dacb0a416229b72c18b19e24a4509f273d26"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:3c112550557578c26af18a1ccc9e090bfe03832ae994343cfdacd287db6a6ae7"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-manylinux1_i686.whl", hash = "sha256:53edb4da6925ad13c07b6d26c2a852bd81e364f95301c66e930ab2aef5b5ddd8"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:f5653a225f31e113b152e56f154ccbe59eeb1c7487b39b9d9f9cdb58e6c79dc5"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-manylinux2010_i686.whl", hash = "sha256:4efca8f86c54b22348a5467704e3fec767b2db12fc39c6d963168ab1d3fc9135"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-manylinux2010_x86_64.whl", hash = "sha256:ab3ef638ace319fa26553db0624c4699e31a28bb2a835c5faca8f8acf6a5a902"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-manylinux2014_aarch64.whl", hash = "sha256:f8ba0e8349a38d3001fae7eadded3f6606f0da5d748ee53cc1dab1d6527b9509"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-win32.whl", hash = "sha256:10f82115e21dc0dfec9ab5c0223652f7197feb168c940f3ef61563fc2d6beb74"},
+    {file = "MarkupSafe-2.0.1-cp39-cp39-win_amd64.whl", hash = "sha256:693ce3f9e70a6cf7d2fb9e6c9d8b204b6b39897a2c4a1aa65728d5ac97dcc1d8"},
+    {file = "MarkupSafe-2.0.1.tar.gz", hash = "sha256:594c67807fb16238b30c44bdf74f36c02cdf22d1c8cda91ef8a0ed8dabf5620a"},
+]
 mccabe = [
     {file = "mccabe-0.6.1-py2.py3-none-any.whl", hash = "sha256:ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42"},
     {file = "mccabe-0.6.1.tar.gz", hash = "sha256:dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"},
@@ -974,6 +1193,10 @@ python-semantic-release = [
     {file = "python-semantic-release-7.19.2.tar.gz", hash = "sha256:8ca0e5f72d31e7b0603b95caad6fb2d5315483ac1fadd86648771966d9ec6f2c"},
     {file = "python_semantic_release-7.19.2-py3-none-any.whl", hash = "sha256:b2c8bb16a643fee0831be4d06138bc1440ebd4f252c3397d41abde179ea56852"},
 ]
+pytz = [
+    {file = "pytz-2021.3-py2.py3-none-any.whl", hash = "sha256:3672058bc3453457b622aab7a1c3bfd5ab0bdae451512f6cf25f64ed37f5b87c"},
+    {file = "pytz-2021.3.tar.gz", hash = "sha256:acad2d8b20a1af07d4e4c9d2e9285c5ed9104354062f275f3fcd88dcef4f1326"},
+]
 pywin32-ctypes = [
     {file = "pywin32-ctypes-0.2.0.tar.gz", hash = "sha256:24ffc3b341d457d48e8922352130cf2644024a4ff09762a2261fd34c36ee5942"},
     {file = "pywin32_ctypes-0.2.0-py2.py3-none-any.whl", hash = "sha256:9dc2d991b3479cc2df15930958b674a48a227d5361d413827a4cfd0b5876fc98"},
@@ -1014,6 +1237,38 @@ smmap = [
     {file = "smmap-4.0.0-py2.py3-none-any.whl", hash = "sha256:a9a7479e4c572e2e775c404dcd3080c8dc49f39918c2cf74913d30c4c478e3c2"},
     {file = "smmap-4.0.0.tar.gz", hash = "sha256:7e65386bd122d45405ddf795637b7f7d2b532e7e401d46bbe3fb49b9986d5182"},
 ]
+snowballstemmer = [
+    {file = "snowballstemmer-2.1.0-py2.py3-none-any.whl", hash = "sha256:b51b447bea85f9968c13b650126a888aabd4cb4463fca868ec596826325dedc2"},
+    {file = "snowballstemmer-2.1.0.tar.gz", hash = "sha256:e997baa4f2e9139951b6f4c631bad912dfd3c792467e2f03d7239464af90e914"},
+]
+sphinx = [
+    {file = "Sphinx-4.2.0-py3-none-any.whl", hash = "sha256:98a535c62a4fcfcc362528592f69b26f7caec587d32cd55688db580be0287ae0"},
+    {file = "Sphinx-4.2.0.tar.gz", hash = "sha256:94078db9184491e15bce0a56d9186e0aec95f16ac20b12d00e06d4e36f1058a6"},
+]
+sphinxcontrib-applehelp = [
+    {file = "sphinxcontrib-applehelp-1.0.2.tar.gz", hash = "sha256:a072735ec80e7675e3f432fcae8610ecf509c5f1869d17e2eecff44389cdbc58"},
+    {file = "sphinxcontrib_applehelp-1.0.2-py2.py3-none-any.whl", hash = "sha256:806111e5e962be97c29ec4c1e7fe277bfd19e9652fb1a4392105b43e01af885a"},
+]
+sphinxcontrib-devhelp = [
+    {file = "sphinxcontrib-devhelp-1.0.2.tar.gz", hash = "sha256:ff7f1afa7b9642e7060379360a67e9c41e8f3121f2ce9164266f61b9f4b338e4"},
+    {file = "sphinxcontrib_devhelp-1.0.2-py2.py3-none-any.whl", hash = "sha256:8165223f9a335cc1af7ffe1ed31d2871f325254c0423bc0c4c7cd1c1e4734a2e"},
+]
+sphinxcontrib-htmlhelp = [
+    {file = "sphinxcontrib-htmlhelp-2.0.0.tar.gz", hash = "sha256:f5f8bb2d0d629f398bf47d0d69c07bc13b65f75a81ad9e2f71a63d4b7a2f6db2"},
+    {file = "sphinxcontrib_htmlhelp-2.0.0-py2.py3-none-any.whl", hash = "sha256:d412243dfb797ae3ec2b59eca0e52dac12e75a241bf0e4eb861e450d06c6ed07"},
+]
+sphinxcontrib-jsmath = [
+    {file = "sphinxcontrib-jsmath-1.0.1.tar.gz", hash = "sha256:a9925e4a4587247ed2191a22df5f6970656cb8ca2bd6284309578f2153e0c4b8"},
+    {file = "sphinxcontrib_jsmath-1.0.1-py2.py3-none-any.whl", hash = "sha256:2ec2eaebfb78f3f2078e73666b1415417a116cc848b72e5172e596c871103178"},
+]
+sphinxcontrib-qthelp = [
+    {file = "sphinxcontrib-qthelp-1.0.3.tar.gz", hash = "sha256:4c33767ee058b70dba89a6fc5c1892c0d57a54be67ddd3e7875a18d14cba5a72"},
+    {file = "sphinxcontrib_qthelp-1.0.3-py2.py3-none-any.whl", hash = "sha256:bd9fc24bcb748a8d51fd4ecaade681350aa63009a347a8c14e637895444dfab6"},
+]
+sphinxcontrib-serializinghtml = [
+    {file = "sphinxcontrib-serializinghtml-1.1.5.tar.gz", hash = "sha256:aa5f6de5dfdf809ef505c4895e51ef5c9eac17d0f287933eb49ec495280b6952"},
+    {file = "sphinxcontrib_serializinghtml-1.1.5-py2.py3-none-any.whl", hash = "sha256:352a9a00ae864471d3a7ead8d7d79f5fc0b57e8b3f95e9867eb9eb28999b92fd"},
+]
 toml = [
     {file = "toml-0.10.2-py2.py3-none-any.whl", hash = "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b"},
     {file = "toml-0.10.2.tar.gz", hash = "sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f"},
diff --git a/pyproject.toml b/pyproject.toml
index d5f09fd..03dfabd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,6 +18,7 @@ coverage = "^5.5"
 pylint = "^2.11.1"
 pyflakes = "^2.3.1"
 pytest = "^6.2.5"
+Sphinx = "^4.2.0"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]
diff --git a/tests/test_checkcert.py b/tests/test_checkcert.py
index de51e41..347dfa3 100644
--- a/tests/test_checkcert.py
+++ b/tests/test_checkcert.py
@@ -50,7 +50,19 @@ def test_san():
 
 def test_san_only():
     """verify --san outputs correctly"""
-    response = runner.invoke(cert_main, ["www.franklin.edu", "--san-only"])
+    check_domain = "franklin.edu"
+    response = runner.invoke(cert_main, ["--san-only", check_domain])
+    assert response.exit_code == 0
+    sep_string = ","
+    response = runner.invoke(
+        cert_main, ["--san-only", f"--sep={sep_string}", check_domain]
+    )
+    assert response.exit_code == 0
+    assert sep_string in response.output
+    sep_string = " -d "
+    response = runner.invoke(
+        cert_main, ["--san-only", f"--sep={sep_string}", check_domain]
+    )
     assert response.exit_code == 0