diff --git a/Library/Homebrew/livecheck.rb b/Library/Homebrew/livecheck.rb
index 10e7a91f99..019612ef17 100644
--- a/Library/Homebrew/livecheck.rb
+++ b/Library/Homebrew/livecheck.rb
@@ -173,7 +173,7 @@ class Livecheck
       url:           T.any(String, Symbol),
       homebrew_curl: T.nilable(T::Boolean),
       post_form:     T.nilable(T::Hash[Symbol, String]),
-      post_json:     T.nilable(T::Hash[Symbol, String]),
+      post_json:     T.nilable(T::Hash[Symbol, T.anything]),
     ).returns(T.nilable(T.any(String, Symbol)))
   }
   def url(url = T.unsafe(nil), homebrew_curl: nil, post_form: nil, post_json: nil)
diff --git a/Library/Homebrew/livecheck/options.rb b/Library/Homebrew/livecheck/options.rb
index 307d393b14..3ef7ca1364 100644
--- a/Library/Homebrew/livecheck/options.rb
+++ b/Library/Homebrew/livecheck/options.rb
@@ -16,7 +16,7 @@ module Homebrew
       prop :post_form, T.nilable(T::Hash[Symbol, String])
 
       # JSON data to use when making a `POST` request.
-      prop :post_json, T.nilable(T::Hash[Symbol, String])
+      prop :post_json, T.nilable(T::Hash[Symbol, T.anything])
 
       # Returns a `Hash` of options that are provided as arguments to `url`.
       sig { returns(T::Hash[Symbol, T.untyped]) }
diff --git a/Library/Homebrew/livecheck/strategy.rb b/Library/Homebrew/livecheck/strategy.rb
index 92b75552fb..0d33d0671d 100644
--- a/Library/Homebrew/livecheck/strategy.rb
+++ b/Library/Homebrew/livecheck/strategy.rb
@@ -174,7 +174,7 @@ module Homebrew
       sig {
         params(
           post_form: T.nilable(T::Hash[Symbol, String]),
-          post_json: T.nilable(T::Hash[Symbol, String]),
+          post_json: T.nilable(T::Hash[Symbol, T.anything]),
         ).returns(T::Array[String])
       }
       def self.post_args(post_form: nil, post_json: nil)