diff --git a/lisp/json.el b/lisp/json.el
index 82cc9c71bf5..7e4c1b05518 100644
--- a/lisp/json.el
+++ b/lisp/json.el
@@ -142,7 +142,7 @@ Used only when `json-encoding-pretty-print' is non-nil.")
   "Sorting predicate for JSON object keys during encoding.
 If nil, no sorting is performed.  Else, JSON object keys are
 ordered by the specified sort predicate during encoding.  For
-instance, setting this to `string<' will have JSON object keys
+instance, setting this to `value<' will have JSON object keys
 ordered alphabetically.")
 
 (defvar json-pre-element-read-function nil
@@ -840,14 +840,14 @@ With prefix argument MINIMIZE, minimize it instead."
   "Pretty-print current buffer with object keys ordered.
 With prefix argument MINIMIZE, minimize it instead."
   (interactive "P")
-  (let ((json-encoding-object-sort-predicate #'string<))
+  (let ((json-encoding-object-sort-predicate #'value<))
     (json-pretty-print-buffer minimize)))
 
 (defun json-pretty-print-ordered (begin end &optional minimize)
   "Pretty-print the region with object keys ordered.
 With prefix argument MINIMIZE, minimize it instead."
   (interactive "r\nP")
-  (let ((json-encoding-object-sort-predicate #'string<))
+  (let ((json-encoding-object-sort-predicate #'value<))
     (json-pretty-print begin end minimize)))
 
 (provide 'json)
diff --git a/test/lisp/json-tests.el b/test/lisp/json-tests.el
index 4fb6a9195ce..9d9df61ee70 100644
--- a/test/lisp/json-tests.el
+++ b/test/lisp/json-tests.el
@@ -657,7 +657,7 @@ Point is moved to beginning of the buffer."
                       "{\n \"c\": 3,\n \"b\": 2,\n \"a\": 1}")))))
 
 (ert-deftest test-json-encode-hash-table-sort ()
-  (let ((json-encoding-object-sort-predicate #'string<)
+  (let ((json-encoding-object-sort-predicate #'value<)
         (json-encoding-pretty-print nil))
     (pcase-dolist (`(,in . ,out)
                    '((#s(hash-table) . "{}")