diff --git a/attribute/generated.go b/attribute/generated.go
index 962e34f..92c1d3e 100644
--- a/attribute/generated.go
+++ b/attribute/generated.go
@@ -636,10 +636,10 @@ func Sizes(value string) hatmill.Attrib {
 }
 
 // Span creates a "span" attribute
-func Span(value string) hatmill.Attrib {
+func Span(value int) hatmill.Attrib {
 	return hatmill.Attrib{
 		Key:   "span",
-		Value: value,
+		Value: strconv.FormatInt(int64(value), 10),
 	}
 }
 
diff --git a/defs.json b/defs.json
index e9521fe..e7992fd 100644
--- a/defs.json
+++ b/defs.json
@@ -81,7 +81,7 @@
     {"name": "shape", "type": "string"},
     {"name": "size", "type": "int"},
     {"name": "sizes", "type": "string"},
-    {"name": "span", "type": "string"},
+    {"name": "span", "type": "int"},
     {"name": "spellcheck", "type": "string"},
     {"name": "src", "type": "string"},
     {"name": "srcdoc", "type": "string"},