diff --git a/tests/parse_test.cpp b/tests/parse_test.cpp
index f058a11..2691690 100644
--- a/tests/parse_test.cpp
+++ b/tests/parse_test.cpp
@@ -121,8 +121,8 @@ int main() {
   assert(hash("tesT") == hash("test"));
   assert(hash("test") != hash("tset"));
 
-  auto percent_decoded = "testing æøå !#$&'()*+,/:;=?@[]";
-  auto percent_encoded = "testing+æøå+%21%23%24%26%27%28%29%2A%2B%2C%2F%3A%3B%3D%3F%40%5B%5D";
+  auto percent_decoded = "testing æøå !#$&'()*+,/:;=?@[]123";
+  auto percent_encoded = "testing+æøå+%21%23%24%26%27%28%29%2A%2B%2C%2F%3A%3B%3D%3F%40%5B%5D123";
   assert(Percent::encode(percent_decoded) == percent_encoded);
   assert(Percent::decode(percent_encoded) == percent_decoded);
   assert(Percent::decode(Percent::encode(percent_decoded)) == percent_decoded);
diff --git a/utility.hpp b/utility.hpp
index b1b33e2..dfb7004 100644
--- a/utility.hpp
+++ b/utility.hpp
@@ -48,7 +48,7 @@ namespace SimpleWeb {
       for(auto &chr : value) {
         if(chr == ' ')
           result += '+';
-        else if(chr == '!' || chr == '#' || chr == '$' || (chr >= '&' && chr <= ',') || (chr >= '/' && chr <= ';') || chr == '=' || chr == '?' || chr == '@' || chr == '[' || chr == ']')
+        else if(chr == '!' || chr == '#' || chr == '$' || (chr >= '&' && chr <= ',') || chr == '/' || chr == ':' || chr == ';' || chr == '=' || chr == '?' || chr == '@' || chr == '[' || chr == ']')
           result += std::string("%") + hex_chars[chr >> 4] + hex_chars[chr & 15];
         else
           result += chr;