diff --git a/std/string/null/len.lb b/std/string/null/len.lb
new file mode 100644
index 0000000..f40bb66
--- /dev/null
+++ b/std/string/null/len.lb
@@ -0,0 +1,11 @@
+@ 0
+ push 0
+
+@ 1
+ args 1
+ jz 2
+ #expr +
+ jmp 1
+
+@ 2
+ quit