diff --git a/Gruntfile.js b/Gruntfile.js
index fda8fd6b..8746c0b6 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -92,7 +92,7 @@ module.exports = function(grunt) {
             },
             tar: {
                 options: {
-                    archive: "build/openseadragon.tar"
+                    archive: "build/openseadragon.tar.gz"
                 },
                 files: [
                    { expand: true, cwd: "build/", src: [ "openseadragon/**" ] }
@@ -177,7 +177,7 @@ module.exports = function(grunt) {
 
     // ----------
     // Package task.
-    // Builds and creates the .zip and .tar files.
+    // Builds and creates the .zip and .tar.gz files.
     grunt.registerTask("package", ["build", "compress"]);
 
     // ----------
diff --git a/README.md b/README.md
index 2bffeb30..5ccbbae3 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ See it in action at http://openseadragon.github.io/.
 
 ## Stable Build
 
-The latest stable builds are here: [Zip](http://openseadragon.github.io/openseadragon.zip) or [Tar](http://openseadragon.github.io/openseadragon.tar).
+The latest stable builds are here: [Zip](http://openseadragon.github.io/openseadragon.zip) or [Tar](http://openseadragon.github.io/openseadragon.tar.gz).
 
 ## First Time Setup
 
@@ -42,7 +42,7 @@ You can also publish the built version to the site-build repository. This assume
 
     grunt publish
 
-... which will delete the existing openseadragon folder, along with the .zip and .tar files, out of the site-build folder and replace them with newly built ones from the source in this repository; you'll then need to commit the changes to site-build.
+... which will delete the existing openseadragon folder, along with the .zip and .tar.gz files, out of the site-build folder and replace them with newly built ones from the source in this repository; you'll then need to commit the changes to site-build.
 
 ## Testing