diff --git a/examples/unit_test.c b/examples/unit_test.c
index 64e350cc649d4ef96959a0deafca9ca828bff953..d0bcdda384b3ab3a4a2ebc3e7eddd870c53fec06 100644
--- a/examples/unit_test.c
+++ b/examples/unit_test.c
@@ -502,6 +502,21 @@ static const char *test_rewrites(void) {
   return NULL;
 }
 
+static const char *test_mg_parse_url(void) {
+  unsigned short port;
+  char a[100], b[100];
+  ASSERT(parse_url("", a, sizeof(a), b, sizeof(b), &port) == 0);
+  ASSERT(parse_url("ws://foo ", a, sizeof(a), b, sizeof(b), &port) == 8);
+  ASSERT(strcmp(a, "ws") == 0 && strcmp(b, "foo") == 0 && port == 80);
+  ASSERT(parse_url("xx://y:123 ", a, sizeof(a), b, sizeof(b), &port) == 10);
+  ASSERT(strcmp(a, "xx") == 0 && strcmp(b, "y") == 0 && port == 123);
+  ASSERT(parse_url(" foo ", a, sizeof(a), b, sizeof(b), &port) == 0);
+  ASSERT(parse_url(" foo:44 ", a, sizeof(a), b, sizeof(b), &port) == 0);
+  ASSERT(parse_url("foo:44 ", a, sizeof(a), b, sizeof(b), &port) == 6);
+  ASSERT(strcmp(a, "") == 0 && strcmp(b, "foo") == 0 && port == 44);
+  return NULL;
+}
+
 static const char *run_all_tests(void) {
   RUN_TEST(test_should_keep_alive);
   RUN_TEST(test_match_prefix);
@@ -518,6 +533,7 @@ static const char *run_all_tests(void) {
   RUN_TEST(test_mg_set_option);
   RUN_TEST(test_server);
   RUN_TEST(test_rewrites);
+  RUN_TEST(test_mg_parse_url);
   return NULL;
 }
 
diff --git a/mongoose.c b/mongoose.c
index ad058a7f4cc206c0a43e06a647625155c9af691d..ac4ce2d68fca5181d07d717e0c104ca8ddacf020 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -3992,11 +3992,12 @@ static int parse_url(const char *url, char *proto, size_t plen,
   snprintf(fmt3, sizeof(fmt3), "%%%zu[^: ]:%%hu%%n", hlen);
 
   if (sscanf(url, fmt1, proto, host, port, &n) == 3 ||
-      sscanf(url, fmt2, proto, host, &n) == 2 ||
-      sscanf(url, fmt3, host, port, &n) == 2) {
+      sscanf(url, fmt2, proto, host, &n) == 2) {
+    return n;
+  } else if (sscanf(url, fmt3, host, port, &n) == 2) {
+    proto[0] = '\0';
     return n;
   }
-
   return 0;
 }