diff --git a/src/main.c b/src/main.c
index 296dab5bbb297bf325705762dc9cd2010efaa7f2..43af0d617d8a40aec7e0efcdd2f60f97f5de6065 100644
--- a/src/main.c
+++ b/src/main.c
@@ -252,7 +252,7 @@ static void help(void)
        "    --data-binary <data>  HTTP POST binary data (H)\n"
        " -D/--dump-header <file> Write the headers to this file\n"
        " -e/--referer       Referer page (H)\n"
-       " -E/--cert <cert:passwd> Specifies your certificate file and password (HTTPS)\n"
+       " -E/--cert <cert[:passwd]> Specifies your certificate file and password (HTTPS)\n"
        "    --cacert <file> CA certifciate to verify peer against (HTTPS)\n"
        " -f/--fail          Fail silently (no output at all) on errors (H)\n"
        " -F/--form <name=content> Specify HTTP POST data (H)\n"
@@ -281,8 +281,8 @@ static void help(void)
        " -S/--show-error    Show error. With -s, make curl show errors when they occur\n"
        " -t/--upload        Transfer/upload stdin to remote site\n"
        " -T/--upload-file <file> Transfer/upload <file> to remote site\n"
-       " -u/--user <user:password> Specify user and password to use\n"
-       " -U/--proxy-user <user:password> Specify Proxy authentication\n"
+       " -u/--user <user[:password]> Specify user and password to use\n"
+       " -U/--proxy-user <user[:password]> Specify Proxy authentication\n"
        " -v/--verbose       Makes the operation more talkative\n"
        " -V/--version       Outputs version number then quits\n"
        " -w/--write-out [format] What to output after completion\n"