diff --git a/README.md b/README.md
index 06805b8..84d415c 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,7 @@ the options are as follows:
 
 - `mod_name.button_icon`:
   A font-awesome class defining the icon used for the toolbar button and
-  actions. See [http://fontawesome.io/icons] for available icon classes.
+  actions. See [fontawesome.io/icons] for available icon classes.
   Defaults to `fa-legal`.
 
 - `mod_name.button_label`:
@@ -276,7 +276,7 @@ History
 [autopep8]: https://github.com/hhatto/autopep8
 [code-prettify]: README_code_prettify.md
 [jupyter-autopep8]: README_autopep8.md
-[http://fontawesome.io/icons]: http://fontawesome.io/icons
+[fontawesome.io/icons]: https://fontawesome.io/icons
 [internals]: #Internals
 [jupyter-autopep8]: https://github.com/kenkoooo/jupyter-autopep8
 [jupyter_nbextensions_configurator]: https://github.com/Jupyter-contrib/jupyter_nbextensions_configurator
diff --git a/README_2to3.md b/README_2to3.md
index 1e0eb4c..53a46a4 100644
--- a/README_2to3.md
+++ b/README_2to3.md
@@ -40,7 +40,7 @@ The options are as follows:
 
 - `2to3.button_icon`:
   A font-awesome class defining the icon used for the toolbar button and
-  actions. See [http://fontawesome.io/icons] for available icon classes.
+  actions. See [fontawesome.io/icons] for available icon classes.
   Defaults to `fa-legal`.
 
 - `2to3.button_label`:
@@ -127,7 +127,7 @@ ways.
 [@takluyver]: https://github.com/takluyver
 [code_prettify]: https://github.com/jfbercher/code_prettify
 [futurize]: http://python-future.org/automatic_conversion.html
-[http://fontawesome.io/icons]: http://fontawesome.io/icons
+[fontawesome.io/icons]: https://fontawesome.io/icons
 [internals]: #Internals
 [jupyter_nbextensions_configurator]: https://github.com/Jupyter-contrib/jupyter_nbextensions_configurator
 [KerneExecOnCells library]: README.md
diff --git a/README_autopep8.md b/README_autopep8.md
index 14d14c9..66c3d95 100644
--- a/README_autopep8.md
+++ b/README_autopep8.md
@@ -46,7 +46,7 @@ The options are as follows:
 
 - `autopep8.button_icon`:
   A font-awesome class defining the icon used for the toolbar button and
-  actions. See [http://fontawesome.io/icons] for available icon classes.
+  actions. See [fontawesome.io/icons] for available icon classes.
   Defaults to `fa-cog`.
 
 - `autopep8.button_label`:
@@ -125,7 +125,7 @@ calls to the active kernel.
 [@kenkoooo]: https://github.com/kenkoooo
 [autopep8]: https://github.com/hhatto/autopep8
 [code_prettify]: https://github.com/jfbercher/code_prettify
-[http://fontawesome.io/icons]: http://fontawesome.io/icons
+[fontawesome.io/icons]: https://fontawesome.io/icons
 [internals]: #Internals
 [jupyter_nbextensions_configurator]: https://github.com/Jupyter-contrib/jupyter_nbextensions_configurator
 [KerneExecOnCells library]: README.md
diff --git a/README_code_prettify.md b/README_code_prettify.md
index e0ac012..e8cf854 100644
--- a/README_code_prettify.md
+++ b/README_code_prettify.md
@@ -95,7 +95,7 @@ The options are as follows:
 
 - `code_prettify.button_icon`:
   A font-awesome class defining the icon used for the toolbar button and
-  actions. See [http://fontawesome.io/icons] for available icon classes.
+  actions. See [fontawesome.io/icons] for available icon classes.
   Defaults to `fa-legal`.
 
 - `code_prettify.button_label`:
@@ -280,17 +280,17 @@ History
 [@jcb91]: https://github.com/jcb91
 [@jfbercher]: https://github.com/jfbercher
 [autopep8]: https://github.com/hhatto/autopep8
-[formatR]: http://yihui.name/formatR
-[http://fontawesome.io/icons]: http://fontawesome.io/icons
-[ijavascript]: http://n-riesco.github.io/ijavascript
+[formatR]: https://yihui.name/formatr
+[fontawesome.io/icons]: https://fontawesome.io/icons
+[ijavascript]: https://n-riesco.github.io/ijavascript
 [internals]: #Internals
 [js-beautify]: https://github.com/beautify-web/js-beautify
-[jsonlite]: https://github.com/jeroenooms/jsonlite
+[jsonlite]: https://github.com/jeroen/jsonlite
 [jupyter_nbextensions_configurator]: https://github.com/Jupyter-contrib/jupyter_nbextensions_configurator
 [KerneExecOnCells library]: README.md
 [kernels]: https://github.com/ipython/ipython/wiki/IPython-kernels-for-other-languages
 [options]: #Options
 [prerequisites]: #Prerequisites
 [README_autopep8.md]: README_autopep8.md
-[this question on stackoverflow]: http://stackoverflow.com/questions/9587665/nodejs-cannot-find-installed-module-on-windows
+[this question on stackoverflow]: https://stackoverflow.com/questions/9587665/nodejs-cannot-find-installed-module-on-windows
 [yapf]: https://github.com/google/yapf