diff --git a/README.md b/README.md
index 5ed8f7c..a7de23a 100644
--- a/README.md
+++ b/README.md
@@ -57,7 +57,7 @@ Legal stuff
 - packJPG v2.5k (https://github.com/packjpg/packJPG) by Matthias Stirner is used for compression/decompression of JPG files.
 - packMP3 v1.0g by Matthias Stirner (http://packjpg.encode.ru/?page_id=19) by Matthias Stirner is used for compression/decompression of MP3 files.
 - bZip2 1.0.6 (http://www.bzip.org) by Julian Seward is used for compression/decompression of bZip2 streams.
-- zLib 1.2.8 (http://www.zlib.net) by Jean-loup Gailly and Mark Adler is used for compression/decompression of zLib streams.
+- zLib 1.2.11 (http://www.zlib.net) by Jean-loup Gailly and Mark Adler is used for compression/decompression of zLib streams.
 - GifLib 4.1.4 (http://sourceforge.net/projects/giflib) is used for compression/decompression of GIF files. The GIFLIB distribution is Copyright (c) 1997 Eric S. Raymond
 - liblzma from XZ Utils 5.2.2 (http://tukaani.org/xz) is used for compression/decompresson of lzma streams.