diff --git a/array/iarray_length.c b/array/iarray_length.c
new file mode 100644
index 0000000..6abbaf3
--- /dev/null
+++ b/array/iarray_length.c
@@ -0,0 +1,5 @@
+#include "iarray.h"
+
+size_t iarray_length(iarray* ia) {
+  return ia->len;
+}