diff --git a/test/any2ppm.c b/test/any2ppm.c
index 5fe8b9efd..bca35f3cd 100644
--- a/test/any2ppm.c
+++ b/test/any2ppm.c
@@ -352,7 +352,7 @@ convert (char **argv, int fd)
     const struct converter *converter = converters;
     char *type;
 
-    type = strchr (argv[0], '.');
+    type = strrchr (argv[0], '.');
     if (type == NULL)
 	return "no file extension";
     type++;