diff --git a/json.h b/json.h
index aa3a316..aeaa7a6 100644
--- a/json.h
+++ b/json.h
@@ -41,5 +41,13 @@ void json_add_double(Json* json, double value);
 void json_add_bool(Json* json, bool value);
 void json_add_null(Json* json);
 
+#define json_add_number(json, value)                       \
+    _Generic(                                              \
+            (value),                                       \
+            int: json_add_long((json), (long)value),       \
+            long: json_add_long((json), value),            \
+            float: json_add_double((json), (double)value), \
+            double: json_add_double((json), value))
+
 #endif // JSON_H
 
diff --git a/tests/json_tests_simple.c b/tests/json_tests_simple.c
index b9b1feb..5d6c02b 100644
--- a/tests/json_tests_simple.c
+++ b/tests/json_tests_simple.c
@@ -64,6 +64,18 @@ void test_json_add_double()
     TEST_ASSERT_EQUAL_STRING("3.14", buffer);
 }
 
+void test_json_add_number()
+{
+    json_add_number(&json, 3.14f);
+    fflush(tmp);
+    rewind(tmp);
+
+    auto n = fread(buffer, 1, sizeof(buffer) - 1, tmp);
+    buffer[n] = '\0';
+
+    TEST_ASSERT_EQUAL_STRING("3.14", buffer);
+}
+
 void test_json_add_bool()
 {
     json_add_bool(&json, true);