diff --git a/README.md b/README.md
index 74fdbbb..41d644b 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,7 @@ HiColor has a Git-style CLI.
 The actions `encode` and `decode` convert images between PNG and HiColor's own image format.  `quantize` round-trips an image through the converter and outputs a normal PNG.  Use it to create images that look high-color but aren't.  `info` displays information about a HiColor file: version (`5` for 15-bit or `6` for 16), width, and height.
 
 ```none
-HiColor 0.4.0
+HiColor 0.5.0
 Create 15/16-bit color RGB images.
 
 usage:
diff --git a/hicolor.h b/hicolor.h
index f18f2f6..fcbf43c 100644
--- a/hicolor.h
+++ b/hicolor.h
@@ -19,7 +19,7 @@
 #include <stdio.h>
 
 #define HICOLOR_BAYER_SIZE 8
-#define HICOLOR_LIBRARY_VERSION 400
+#define HICOLOR_LIBRARY_VERSION 500
 
 /* Types. */