diff --git a/duniterpy/api/client.py b/duniterpy/api/client.py
index a5fa7fa20d6fc7c0fe9aeba8a2763297cb3c0eef..f527548a668c117b300552ee6162b78c6a749bb7 100644
--- a/duniterpy/api/client.py
+++ b/duniterpy/api/client.py
@@ -322,7 +322,7 @@ class API:
         elif _json is not None:
             logging.debug("%s : %s, json=%s", method, url, _json)
             # http header to send json body
-            self.headers["Content-Type"] = "application/json; charset=utf-8"
+            self.headers["Content-Type"] = "application/json"
         else:
             logging.debug("%s : %s", method, url)