diff --git a/MANIFEST.in b/MANIFEST.in
index 62af6e7f..b56caaea 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -7,6 +7,7 @@ include onionshare/404.html
 include onionshare/strings.json
 include onionshare_gui/templates/index.html
 include onionshare_gui/static/jquery-1.11.1.min.js
+include onionshare_gui/static/helpers.js
 include onionshare_gui/static/onionshare.js
 include onionshare_gui/static/style.css
 include onionshare_gui/static/loader.gif
diff --git a/onionshare/onionshare.py b/onionshare/onionshare.py
index c84e24b9..1b0895cb 100644
--- a/onionshare/onionshare.py
+++ b/onionshare/onionshare.py
@@ -27,30 +27,62 @@ def set_file_info(new_filename, new_filehash, new_filesize):
 
 REQUEST_LOAD = 0
 REQUEST_DOWNLOAD = 1
-REQUEST_OTHER = 2
+REQUEST_PROGRESS = 2
+REQUEST_OTHER = 3
 request_q = Queue.Queue()
 
-def add_request(type):
+download_count = 0
+
+def add_request(type, path, data=None):
     global request_q
     request_q.put({
       'type': type,
-      'path': request.path
+      'path': path,
+      'data': data
     })
 
 @app.route("/{0}".format(slug))
 def index():
     global filename, filesize, filehash, slug, strings, REQUEST_LOAD
-    add_request(REQUEST_LOAD)
+    add_request(REQUEST_LOAD, request.path)
     return render_template_string(open('{0}/index.html'.format(os.path.dirname(__file__))).read(),
         slug=slug, filename=os.path.basename(filename), filehash=filehash, filesize=filesize, strings=strings)
 
 @app.route("/{0}/download".format(slug))
 def download():
-    global filename, request_q, REQUEST_DOWNLOAD
-    add_request(REQUEST_DOWNLOAD)
+    global filename, filesize, request_q, download_count
+    global REQUEST_DOWNLOAD, REQUEST_PROGRESS
+
+    # each download has a unique id
+    download_id = download_count
+    download_count += 1
+
+    # tell GUI the download started
+    path = request.path
+    add_request(REQUEST_DOWNLOAD, path, { 'id':download_id })
+
     dirname = os.path.dirname(filename)
     basename = os.path.basename(filename)
-    return send_from_directory(dirname, basename, as_attachment=True)
+
+    def generate():
+        chunk_size = 102400 # 100kb
+
+        fp = open(filename, 'rb')
+        done = False
+        while not done:
+            chunk = fp.read(102400)
+            if chunk == '':
+                done = True
+            yield chunk
+            
+            # tell GUI the progress
+            add_request(REQUEST_PROGRESS, path, { 'id':download_id, 'bytes':fp.tell() })
+        fp.close()
+
+    r = Response(generate())
+    r.headers.add('Content-Length', filesize)
+    r.headers.add('Content-Disposition', 'attachment', filename=basename)
+    return r
 
 @app.errorhandler(404)
 def page_not_found(e):
diff --git a/onionshare_gui/static/helpers.js b/onionshare_gui/static/helpers.js
new file mode 100644
index 00000000..951320ba
--- /dev/null
+++ b/onionshare_gui/static/helpers.js
@@ -0,0 +1,11 @@
+function human_readable_filesize(bytes, si) {
+  var thresh = si ? 1000 : 1024;
+  if(bytes < thresh) return bytes + ' B';
+  var units = si ? ['kB','MB','GB','TB','PB','EB','ZB','YB'] : ['KiB','MiB','GiB','TiB','PiB','EiB','ZiB','YiB'];
+  var u = -1;
+  do {
+    bytes /= thresh;
+    ++u;
+  } while(bytes >= thresh);
+  return bytes.toFixed(1)+' '+units[u];
+};
diff --git a/onionshare_gui/static/onionshare.js b/onionshare_gui/static/onionshare.js
index c8cf3125..42c9120f 100644
--- a/onionshare_gui/static/onionshare.js
+++ b/onionshare_gui/static/onionshare.js
@@ -21,7 +21,8 @@ $(function(){
 
   var REQUEST_LOAD = 0;
   var REQUEST_DOWNLOAD = 1;
-  var REQUEST_OTHER = 2;
+  var REQUEST_PROGRESS = 2;
+  var REQUEST_OTHER = 3;
   function check_for_requests() {
     $.ajax({
       url: '/check_for_requests',
@@ -31,7 +32,14 @@ $(function(){
           if(r.type == REQUEST_LOAD) {
             update($('<span>').addClass('weblog').html(onionshare.strings['download_page_loaded']));
           } else if(r.type == REQUEST_DOWNLOAD) {
-            update($('<span>').addClass('weblog').html(onionshare.strings['download_started']));
+            var $download = $('<span>')
+              .attr('id', 'download-'+r.data.id)
+              .addClass('weblog').html(onionshare.strings['download_started'])
+              .append($('<span>').addClass('progress'));
+            update($download);
+          } else if(r.type == REQUEST_PROGRESS) {
+              var percent = Math.floor((r.data.bytes / onionshare.filesize) * 100);
+              $('#download-'+r.data.id+' .progress').html(' '+human_readable_filesize(r.data.bytes)+', '+percent+'%');
           } else {
             if(r.path != '/favicon.ico')
               update($('<span>').addClass('weblog-error').html(onionshare.strings['other_page_loaded']+': '+r.path));
@@ -65,7 +73,7 @@ $(function(){
 
           $('#loading').remove();
 
-          $('#filesize .value').html(onionshare.filesize+' bytes');
+          $('#filesize .value').html(human_readable_filesize(onionshare.filesize));
           $('#filehash .value').html(onionshare.filehash);
           $('#filesize').show(500);
           $('#filehash').show(500);
diff --git a/onionshare_gui/templates/index.html b/onionshare_gui/templates/index.html
index a3bb0a0a..d0fe467c 100644
--- a/onionshare_gui/templates/index.html
+++ b/onionshare_gui/templates/index.html
@@ -29,6 +29,7 @@
       </ul>
     </ul>
     <script src="static/jquery-1.11.1.min.js"></script>
+    <script src="static/helpers.js"></script>
     <script src="static/onionshare.js"></script>
   </body>
 </html>