diff --git a/Makefile b/Makefile
index 5562e43..86e98c5 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,7 @@ MANDIR = $(PREFIX)/share/man/man1
 
 LDFLAGS != pkg-config --libs libsixel
 INCFLAGS != pkg-config --cflags libsixel
-CFLAGS = -O3 -march=native -mtune=native -pipe -s -flto -std=c99 -pedantic -Wall -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 $(INCFLAGS)
+CFLAGS = -Os -march=native -mtune=native -pipe -s -flto -std=c99 -pedantic -Wall -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 $(INCFLAGS)
 
 SRC = ccc.c util.c file.c icons.c