diff --git a/unit_tests/util/json_render.cpp b/unit_tests/util/json_render.cpp
index dcf0076e9..749416cad 100644
--- a/unit_tests/util/json_render.cpp
+++ b/unit_tests/util/json_render.cpp
@@ -32,6 +32,62 @@ BOOST_AUTO_TEST_CASE(test_json_issue_6531) {
     osrm::util::json::Renderer<std::string> renderer(output);
     renderer(0.0000000000017114087924596788);
     BOOST_CHECK_EQUAL(output, "1.711408792e-12");
+
+    output.clear();
+    renderer(42.0);
+    BOOST_CHECK_EQUAL(output, "42");
+
+    output.clear();
+    renderer(42.1);
+    BOOST_CHECK_EQUAL(output, "42.1");
+
+    output.clear();
+    renderer(42.12);
+    BOOST_CHECK_EQUAL(output, "42.12");
+
+    output.clear();
+    renderer(42.123);
+    BOOST_CHECK_EQUAL(output, "42.123");
+
+    output.clear();
+    renderer(42.1234);
+    BOOST_CHECK_EQUAL(output, "42.1234");
+
+    output.clear();
+    renderer(42.12345);
+    BOOST_CHECK_EQUAL(output, "42.12345");
+
+    output.clear();
+    renderer(42.123456);
+    BOOST_CHECK_EQUAL(output, "42.123456");
+
+    output.clear();
+    renderer(42.1234567);
+    BOOST_CHECK_EQUAL(output, "42.1234567");
+
+    output.clear();
+    renderer(42.12345678);
+    BOOST_CHECK_EQUAL(output, "42.12345678");
+
+    output.clear();
+    renderer(42.123456789);
+    BOOST_CHECK_EQUAL(output, "42.12345679");
+
+    output.clear();
+    renderer(0.12345678912345);
+    BOOST_CHECK_EQUAL(output, "0.1234567891");
+
+    output.clear();
+    renderer(0.123456789);
+    BOOST_CHECK_EQUAL(output, "0.123456789");
+
+    output.clear();
+    renderer(0.12345678916);
+    BOOST_CHECK_EQUAL(output, "0.1234567892");
+
+    output.clear();
+    renderer(123456789123456789);
+    BOOST_CHECK_EQUAL(output, "1.234567891e+17");
 }
 
 BOOST_AUTO_TEST_SUITE_END()