diff --git a/grammars/json.gbnf b/grammars/json.gbnf
index b6448c87b7..3692923e62 100644
--- a/grammars/json.gbnf
+++ b/grammars/json.gbnf
@@ -19,7 +19,7 @@ string ::=
     "\\" (["\\bfnrt] | "u" [0-9a-fA-F]{4}) # escapes
   )* "\"" ws
 
-number ::= ("-"? ([0-9] | [1-9] [0-9]{0,15})) ("." [0-9]+)? ([eE] [-+]? [0-9] [1-9]{0,15})? ws
+number ::= ("-"? ([0-9] | [1-9] [0-9]{0,15})) ("." [0-9]+)? ([eE] [-+]? [1-9] [0-9]{0,15})? ws
 
 # Optional space: by convention, applied in this grammar after literal chars when allowed
 ws ::= | " " | "\n" [ \t]{0,20}