diff --git a/README.md b/README.md
index b99c70099..c343ddf0f 100644
--- a/README.md
+++ b/README.md
@@ -46,7 +46,7 @@ To get a local copy of the current code, clone it using git:
     $ git clone https://github.com/mozilla/pdf.js.git
     $ cd pdf.js
 
-Next, install Node.js via the [official package](http://nodejs.org) or via
+Next, install Node.js via the [official package](https://nodejs.org) or via
 [nvm](https://github.com/creationix/nvm). You need to install the gulp package
 globally (see also [gulp's getting started](https://github.com/gulpjs/gulp/blob/master/docs/getting-started.md#getting-started)):
 
@@ -100,14 +100,14 @@ PDF.js is hosted on several free CDNs:
 
 You can play with the PDF.js API directly from your browser using the live demos below:
 
-+ [Interactive examples](http://mozilla.github.io/pdf.js/examples/index.html#interactive-examples)
++ [Interactive examples](https://mozilla.github.io/pdf.js/examples/index.html#interactive-examples)
 
 More examples can be found in the [examples folder](https://github.com/mozilla/pdf.js/tree/master/examples/). Some of them are using the pdfjs-dist package, which can be built and installed in this repo directory via `gulp dist-install` command.
 
 For an introduction to the PDF.js code, check out the presentation by our
 contributor Julian Viereck:
 
-+ http://www.youtube.com/watch?v=Iv15UY-4Fg8
++ https://www.youtube.com/watch?v=Iv15UY-4Fg8
 
 More learning resources can be found at:
 
@@ -129,4 +129,4 @@ File an issue:
 
 Follow us on twitter: @pdfjs
 
-+ http://twitter.com/#!/pdfjs
++ https://twitter.com/pdfjs