diff --git a/src/yamlhttpforms/form.py b/src/yamlhttpforms/form.py
index edeb755..9d69b07 100644
--- a/src/yamlhttpforms/form.py
+++ b/src/yamlhttpforms/form.py
@@ -29,8 +29,10 @@ class FormField:
                 obj = getattr(obj, attr)
             self._default = obj
         else:
-            self._default = default
-        self.options: Optional[OptionsT] = options
+            self._default = str(default)
+        self.options: Optional[OptionsT] = None
+        if options is not None:
+            self.options = {str(k): str(v) for k, v in options.items()}
         self.required: bool = required
 
     def __repr__(self) -> str: