diff --git a/types/uint.yaml b/types/uint.yaml
index 24f4e88..c62a9c3 100644
--- a/types/uint.yaml
+++ b/types/uint.yaml
@@ -1,4 +1,4 @@
 Uint64:
   type: string
-  pattern: ^[1-9][0-9]{0,19}$
+  pattern: ^(0|[1-9][0-9]{0,19})$
   example: "30000000"