diff --git a/README.md b/README.md
index eacf653..d69dea5 100644
--- a/README.md
+++ b/README.md
@@ -18,7 +18,7 @@ If you cannot see templates in your HACS listing, you *may* need to enable 'expe
 
 # Availability Test
 
-## `avail([entity1, ...])`
+## `avail([entity1, entity2, /])`
 
 This expects a list of entities.
 
diff --git a/availability_template.jinja b/availability_template.jinja
index 548102f..d042de6 100644
--- a/availability_template.jinja
+++ b/availability_template.jinja
@@ -13,7 +13,10 @@
       {% from 'availability_template.jinja' import avail %}
       {{- avail(['entity_1','entity_2']) | bool -}}
   #}
-  {%- if entity_list is iterable -%}
+  {# First tests to make sure this is a list #}
+  {%- if entity_list is iterable and
+    (entity_list is not string and entity_list is not mapping)
+  -%}
     {{- entity_list | map('states') | reject('in', ['unknown','unavailable','','none'])
     | list | count == entity_list | count -}}
   {%- else -%}