diff --git a/internal/common/common.go b/internal/common/common.go
index ddab88b..69551bc 100644
--- a/internal/common/common.go
+++ b/internal/common/common.go
@@ -1,8 +1,13 @@
 package common
 
+const charsetUTF8 = "charset=UTF-8"
+
 const (
-	MIMEApplicationJSON               string = "application/json"
-	MIMEApplicationXWWWFormUrlencoded string = "application/x-www-form-urlencoded"
-	MIMETextHTML                      string = "text/html"
-	MIMETextPlain                     string = "text/plain"
+	MIMEApplicationForm            string = "application/x-www-form-urlencoded"
+	MIMEApplicationJSON            string = "application/json"
+	MIMEApplicationJSONCharsetUTF8 string = MIMEApplicationJSON + "; " + charsetUTF8
+	MIMETextHTML                   string = "text/html"
+	MIMETextHTMLCharsetUTF8        string = MIMETextHTML + "; " + charsetUTF8
+	MIMETextPlain                  string = "text/plain"
+	MIMETextPlainCharsetUTF8       string = MIMETextPlain + "; " + charsetUTF8
 )