diff --git a/include/date/ptz.h b/include/date/ptz.h
index ebd6e04..3ea3e47 100644
--- a/include/date/ptz.h
+++ b/include/date/ptz.h
@@ -678,6 +678,8 @@ read_date(const string_t& s, unsigned i, rule& r)
         ++i;
         unsigned n;
         i = read_unsigned(s, i, 3, n, "Expected to find the Julian day [1, 365]");
+        if (!(1 <= n && n <= 365))
+            throw_invalid(s, i-1, "Expected Julian day to be in the range [1, 365]");
         r.mode_ = rule::J;
         r.n_ = n;
     }
@@ -686,16 +688,22 @@ read_date(const string_t& s, unsigned i, rule& r)
         ++i;
         unsigned m;
         i = read_unsigned(s, i, 2, m, "Expected to find month [1, 12]");
+        if (!(1 <= m && m <= 12))
+            throw_invalid(s, i-1, "Expected month to be in the range [1, 12]");
         if (i == s.size() || s[i] != '.')
             throw_invalid(s, i, "Expected '.' after month");
         ++i;
         unsigned n;
         i = read_unsigned(s, i, 1, n, "Expected to find week number [1, 5]");
+        if (!(1 <= n && n <= 5))
+            throw_invalid(s, i-1, "Expected week number to be in the range [1, 5]");
         if (i == s.size() || s[i] != '.')
             throw_invalid(s, i, "Expected '.' after weekday index");
         ++i;
         unsigned wd;
         i = read_unsigned(s, i, 1, wd, "Expected to find day of week [0, 6]");
+        if (wd > 6)
+            throw_invalid(s, i-1, "Expected day of week to be in the range [0, 6]");
         r.mode_ = rule::M;
         r.m_ = month{m};
         r.wd_ = weekday{wd};
@@ -705,6 +713,8 @@ read_date(const string_t& s, unsigned i, rule& r)
     {
         unsigned n;
         i = read_unsigned(s, i, 3, n);
+        if (n > 365)
+            throw_invalid(s, i-1, "Expected Julian day to be in the range [0, 365]");
         r.mode_ = rule::N;
         r.n_ = n;
     }
@@ -786,16 +796,22 @@ read_unsigned_time(const string_t& s, unsigned i, std::chrono::seconds& t)
         throw_invalid(s, i, "Expected to read unsigned time, but found end of string");
     unsigned x;
     i = read_unsigned(s, i, 2, x, "Expected to find hours [0, 24]");
+    if (x > 24)
+        throw_invalid(s, i-1, "Expected hours to be in the range [0, 24]");
     t = hours{x};
     if (i != s.size() && s[i] == ':')
     {
         ++i;
         i = read_unsigned(s, i, 2, x, "Expected to find minutes [0, 59]");
+        if (x > 59)
+            throw_invalid(s, i-1, "Expected minutes to be in the range [0, 59]");
         t += minutes{x};
         if (i != s.size() && s[i] == ':')
         {
             ++i;
             i = read_unsigned(s, i, 2, x, "Expected to find seconds [0, 59]");
+            if (x > 59)
+                throw_invalid(s, i-1, "Expected seconds to be in the range [0, 59]");
             t += seconds{x};
         }
     }