diff --git a/core/io/json.cpp b/core/io/json.cpp
index 0582329bc39..34f001a2282 100644
--- a/core/io/json.cpp
+++ b/core/io/json.cpp
@@ -73,18 +73,18 @@ void JSON::_stringify(String &r_result, const Variant &p_var, const String &p_in
 			r_result += itos(p_var);
 			return;
 		case Variant::FLOAT: {
-			double num = p_var;
+			const double num = p_var;
 
 			// Only for exactly 0. If we have approximately 0 let the user decide how much
 			// precision they want.
-			if (num == double(0)) {
+			if (num == double(0.0)) {
 				r_result += "0.0";
 				return;
 			}
 
-			double magnitude = std::log10(Math::abs(num));
-			int total_digits = p_full_precision ? 17 : 14;
-			int precision = MAX(1, total_digits - (int)Math::floor(magnitude));
+			const double magnitude = std::log10(Math::abs(num));
+			const int total_digits = p_full_precision ? 17 : 14;
+			const int precision = MAX(1, total_digits - (int)Math::floor(magnitude));
 
 			r_result += String::num(num, precision);
 			return;
@@ -120,7 +120,7 @@ void JSON::_stringify(String &r_result, const Variant &p_var, const String &p_in
 					r_result += end_statement;
 				}
 				_add_indent(r_result, p_indent, p_cur_indent + 1);
-				_stringify(r_result, var, p_indent, p_cur_indent + 1, p_sort_keys, p_markers);
+				_stringify(r_result, var, p_indent, p_cur_indent + 1, p_sort_keys, p_markers, p_full_precision);
 			}
 			r_result += end_statement;
 			_add_indent(r_result, p_indent, p_cur_indent);
@@ -154,9 +154,9 @@ void JSON::_stringify(String &r_result, const Variant &p_var, const String &p_in
 					r_result += end_statement;
 				}
 				_add_indent(r_result, p_indent, p_cur_indent + 1);
-				_stringify(r_result, String(key), p_indent, p_cur_indent + 1, p_sort_keys, p_markers);
+				_stringify(r_result, String(key), p_indent, p_cur_indent + 1, p_sort_keys, p_markers, p_full_precision);
 				r_result += colon;
-				_stringify(r_result, d[key], p_indent, p_cur_indent + 1, p_sort_keys, p_markers);
+				_stringify(r_result, d[key], p_indent, p_cur_indent + 1, p_sort_keys, p_markers, p_full_precision);
 			}
 
 			r_result += end_statement;
diff --git a/core/io/json.h b/core/io/json.h
index 06edeffac10..1703393c4d0 100644
--- a/core/io/json.h
+++ b/core/io/json.h
@@ -72,7 +72,7 @@ class JSON : public Resource {
 	static const char *tk_name[];
 
 	static void _add_indent(String &r_result, const String &p_indent, int p_size);
-	static void _stringify(String &r_result, const Variant &p_var, const String &p_indent, int p_cur_indent, bool p_sort_keys, HashSet<const void *> &p_markers, bool p_full_precision = false);
+	static void _stringify(String &r_result, const Variant &p_var, const String &p_indent, int p_cur_indent, bool p_sort_keys, HashSet<const void *> &p_markers, bool p_full_precision);
 	static Error _get_token(const char32_t *p_str, int &index, int p_len, Token &r_token, int &line, String &r_err_str);
 	static Error _parse_value(Variant &value, Token &token, const char32_t *p_str, int &index, int p_len, int &line, int p_depth, String &r_err_str);
 	static Error _parse_array(Array &array, const char32_t *p_str, int &index, int p_len, int &line, int p_depth, String &r_err_str);
diff --git a/tests/core/io/test_json.h b/tests/core/io/test_json.h
index 87448a24bcb..3da156c7681 100644
--- a/tests/core/io/test_json.h
+++ b/tests/core/io/test_json.h
@@ -71,6 +71,10 @@ TEST_CASE("[JSON] Stringify arrays") {
 	indented_array.push_back(nested_array);
 	CHECK(JSON::stringify(indented_array, "\t") == "[\n\t0,\n\t1,\n\t2,\n\t3,\n\t4,\n\t[\n\t\t0,\n\t\t1,\n\t\t2,\n\t\t3,\n\t\t4\n\t]\n]");
 
+	Array full_precision_array;
+	full_precision_array.push_back(0.123456789012345677);
+	CHECK(JSON::stringify(full_precision_array, "", true, true) == "[0.123456789012345677]");
+
 	ERR_PRINT_OFF
 	Array self_array;
 	self_array.push_back(self_array);
@@ -105,6 +109,10 @@ TEST_CASE("[JSON] Stringify dictionaries") {
 	outer["inner"] = inner;
 	CHECK(JSON::stringify(outer) == "{\"inner\":{\"key\":\"value\"}}");
 
+	Dictionary full_precision_dictionary;
+	full_precision_dictionary["key"] = 0.123456789012345677;
+	CHECK(JSON::stringify(full_precision_dictionary, "", true, true) == "{\"key\":0.123456789012345677}");
+
 	ERR_PRINT_OFF
 	Dictionary self_dictionary;
 	self_dictionary["key"] = self_dictionary;