diff --git a/README.md b/README.md
index 12188dcb..bc3411ef 100644
--- a/README.md
+++ b/README.md
@@ -19,15 +19,15 @@ Markups
 The following markups are supported.  The dependencies listed are required if
 you wish to run the library. You can also run `script/bootstrap` to fetch them all.
 
-* [.markdown, .mdown, .mkdn, .md](http://daringfireball.net/projects/markdown/) -- `gem install commonmarker` (https://github.com/gjtorikian/commonmarker)
+* [.markdown, .mdown, .mkdn, .md](https://daringfireball.net/projects/markdown/) -- `gem install commonmarker` (https://github.com/gjtorikian/commonmarker)
 * [.textile](https://textile-lang.com/) -- `gem install RedCloth` (https://github.com/jgarber/redcloth)
 * [.rdoc](https://ruby.github.io/rdoc/) -- `gem install rdoc -v 3.6.1`
-* [.org](http://orgmode.org/) -- `gem install org-ruby` (https://github.com/wallyqs/org-ruby)
-* [.creole](http://wikicreole.org/) -- `gem install creole` (https://github.com/larsch/creole)
-* [.mediawiki, .wiki](http://www.mediawiki.org/wiki/Help:Formatting) -- `gem install wikicloth` (https://github.com/nricciar/wikicloth)
-* [.rst](http://docutils.sourceforge.net/rst.html) -- `pip install docutils`
-* [.asciidoc, .adoc, .asc](http://asciidoc.org/) -- `gem install asciidoctor` (http://asciidoctor.org)
-* [.pod](http://search.cpan.org/dist/perl/pod/perlpod.pod) -- `Pod::Simple::XHTML`
+* [.org](https://orgmode.org/) -- `gem install org-ruby` (https://github.com/wallyqs/org-ruby)
+* [.creole](https://wikicreole.org/) -- `gem install creole` (https://github.com/larsch/creole)
+* [.mediawiki, .wiki](https://www.mediawiki.org/wiki/Help:Formatting) -- `gem install wikicloth` (https://github.com/nricciar/wikicloth)
+* [.rst](https://docutils.sourceforge.net/rst.html) -- `pip install docutils`
+* [.asciidoc, .adoc, .asc](https://asciidoc.org/) -- `gem install asciidoctor` (https://asciidoctor.org)
+* [.pod](https://search.cpan.org/dist/perl/pod/perlpod.pod) -- `Pod::Simple::XHTML`
   comes with Perl >= 5.10. Lower versions should install Pod::Simple from CPAN.
 
 Installation