diff --git a/generate_emoji_thumbnails.py b/generate_emoji_thumbnails.py
new file mode 100755
index 000000000..f66fa6a3a
--- /dev/null
+++ b/generate_emoji_thumbnails.py
@@ -0,0 +1,126 @@
+#!/usr/bin/env python
+# Copyright 2017 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Generate 72x72 thumbnails including aliases.
+
+Takes a source directory of images named using our emoji filename
+conventions and writes thumbnails of them into the destination
+directory.  If a file is a target of one or more aliases, creates
+copies named for the aliases."""
+
+
+import argparse
+import collections
+import logging
+import os
+from os import path
+import shutil
+import subprocess
+
+import add_aliases
+
+from nototools import tool_utils
+
+logger = logging.getLogger('emoji_thumbnails')
+
+def create_thumbnail(src_path, dst_path):
+  # uses imagemagik
+  subprocess.check_call(['convert', '-resize', '72x72', src_path, dst_path])
+  logger.info('wrote thumbnail: %s' % dst_path)
+
+
+_INV_ALIASES = None
+def get_inv_aliases():
+  global _INV_ALIASES
+  if _INV_ALIASES is None:
+    aliases = add_aliases.read_default_emoji_aliases()
+    inv_aliases = collections.defaultdict(list)
+    for k, v in aliases.iteritems():
+      inv_aliases[v].append(k)
+    _INV_ALIASES = inv_aliases
+  return _INV_ALIASES
+
+
+def is_emoji_filename(filename):
+  return filename.startswith('emoji_u') and filename.endswith('.png')
+
+
+def check_emoji_filename(filename):
+  if not is_emoji_filename(filename):
+    raise ValueError('not an emoji image file: %s' % filename)
+
+
+def emoji_filename_to_sequence(filename):
+  check_emoji_filename(filename)
+
+  return tuple([
+      int(s, 16) for s in filename[7:-4].split('_')
+      if s.lower() != 'fe0f'])
+
+
+def sequence_to_emoji_filename(seq):
+  return 'emoji_u%s.png' % '_'.join('%04x' % n for n in seq)
+
+
+def create_emoji_alias(src_path, dst_dir):
+  """If src_path is a target of any emoji aliases, create a copy in dst_dir
+  named for each alias."""
+  src_file = path.basename(src_path)
+  seq = emoji_filename_to_sequence(src_file)
+
+  inv_aliases = get_inv_aliases()
+  if seq in inv_aliases:
+    for alias_seq in inv_aliases[seq]:
+      alias_file = sequence_to_emoji_filename(alias_seq)
+      shutil.copy2(src_path, path.join(dst_dir, alias_file))
+      logger.info('wrote alias %s (copy of %s)' % (alias_file, src_file))
+
+
+def create_thumbnails_and_aliases(src_dir, dst_dir):
+  if not path.isdir(src_dir):
+    raise ValueError('"%s" is not a directory')
+  dst_dir = tool_utils.ensure_dir_exists(dst_dir)
+
+  for f in os.listdir(src_dir):
+    if not (f.startswith('emoji_u') and f.endswith('.png')):
+      logger.warning('skipping "%s"' % f)
+      continue
+    src = path.join(src_dir, f)
+    dst = path.join(dst_dir, f)
+    create_thumbnail(src, dst)
+    create_emoji_alias(dst, dst_dir)
+
+
+def main():
+  parser = argparse.ArgumentParser()
+  parser.add_argument(
+      '-s', '--src_dir', help='source images', metavar='dir', required=True)
+  parser.add_argument(
+      '-d', '--dst_dir', help='destination directory', metavar='dir',
+      required=True)
+  parser.add_argument(
+      '-v', '--verbose', help='write log output', metavar='level',
+      choices='warning info debug'.split(), const='info',
+      nargs='?')
+  args = parser.parse_args()
+
+  if args.verbose is not None:
+    logging.basicConfig(level=getattr(logging, args.verbose.upper()))
+
+  create_thumbnails_and_aliases(args.src_dir, args.dst_dir)
+
+
+if __name__ == '__main__':
+  main()