diff --git a/tdutils/td/utils/port/IPAddress.cpp b/tdutils/td/utils/port/IPAddress.cpp
index 38f06736..d773ec2a 100644
--- a/tdutils/td/utils/port/IPAddress.cpp
+++ b/tdutils/td/utils/port/IPAddress.cpp
@@ -12,6 +12,7 @@
 #include "td/utils/port/SocketFd.h"
 #include "td/utils/port/thread_local.h"
 #include "td/utils/ScopeGuard.h"
+#include "td/utils/Slice.h"
 #include "td/utils/utf8.h"
 
 #if TD_WINDOWS
@@ -23,6 +24,7 @@
 #endif
 
 #include <cstring>
+#include <limits>
 
 namespace td {
 
@@ -175,6 +177,38 @@ bool IPAddress::is_valid() const {
   return is_valid_;
 }
 
+bool IPAddress::is_reserved() const {
+  CHECK(is_valid());
+
+  if (is_ipv6()) {
+    // TODO proper check for reserved IPv6 addresses
+    return true;
+  }
+
+  uint32 ip = get_ipv4();
+  struct IpBlock {
+    CSlice ip;
+    int mask;
+    IpBlock(CSlice ip, int mask) : ip(ip), mask(mask) {
+    }
+  };
+  static const IpBlock blocks[] = {{"0.0.0.0", 8},      {"10.0.0.0", 8},     {"100.64.0.0", 10}, {"127.0.0.0", 8},
+                                   {"169.254.0.0", 16}, {"172.16.0.0", 12},  {"192.0.0.0", 24},  {"192.0.2.0", 24},
+                                   {"192.88.99.0", 24}, {"192.168.0.0", 16}, {"198.18.0.0", 15}, {"198.51.100.0", 24},
+                                   {"203.0.113.0", 24}, {"224.0.0.0", 3}};
+  for (auto &block : blocks) {
+    IPAddress block_ip_address;
+    block_ip_address.init_ipv4_port(block.ip, 80).ensure();
+    uint32 range = block_ip_address.get_ipv4();
+    CHECK(block.mask != 0);
+    uint32 mask = std::numeric_limits<uint32>::max() >> (32 - block.mask) << (32 - block.mask);
+    if ((ip & mask) == (range & mask)) {
+      return true;
+    }
+  }
+  return false;
+}
+
 const sockaddr *IPAddress::get_sockaddr() const {
   CHECK(is_valid());
   return &sockaddr_;
diff --git a/tdutils/td/utils/port/IPAddress.h b/tdutils/td/utils/port/IPAddress.h
index 9d6082e6..6e62e737 100644
--- a/tdutils/td/utils/port/IPAddress.h
+++ b/tdutils/td/utils/port/IPAddress.h
@@ -33,6 +33,8 @@ class IPAddress {
   bool is_ipv4() const;
   bool is_ipv6() const;
 
+  bool is_reserved() const;
+
   int get_port() const;
   void set_port(int port);
 
diff --git a/tdutils/test/misc.cpp b/tdutils/test/misc.cpp
index aacebf5a..8ebcde2c 100644
--- a/tdutils/test/misc.cpp
+++ b/tdutils/test/misc.cpp
@@ -454,6 +454,73 @@ TEST(Misc, IPAddress_get_ipv4) {
   test_get_ipv4(0xFFFFFFFF);
 }
 
+static void test_is_reserved(string ip, bool is_reserved) {
+  IPAddress ip_address;
+  ip_address.init_ipv4_port(ip, 80).ensure();
+  ASSERT_EQ(is_reserved, ip_address.is_reserved());
+}
+
+TEST(Misc, IPAddress_is_reserved) {
+  test_is_reserved("0.0.0.0", true);
+  test_is_reserved("0.255.255.255", true);
+  test_is_reserved("1.0.0.0", false);
+  test_is_reserved("5.0.0.0", false);
+  test_is_reserved("9.255.255.255", false);
+  test_is_reserved("10.0.0.0", true);
+  test_is_reserved("10.255.255.255", true);
+  test_is_reserved("11.0.0.0", false);
+  test_is_reserved("100.63.255.255", false);
+  test_is_reserved("100.64.0.0", true);
+  test_is_reserved("100.127.255.255", true);
+  test_is_reserved("100.128.0.0", false);
+  test_is_reserved("126.255.255.255", false);
+  test_is_reserved("127.0.0.0", true);
+  test_is_reserved("127.255.255.255", true);
+  test_is_reserved("128.0.0.0", false);
+  test_is_reserved("169.253.255.255", false);
+  test_is_reserved("169.254.0.0", true);
+  test_is_reserved("169.254.255.255", true);
+  test_is_reserved("169.255.0.0", false);
+  test_is_reserved("172.15.255.255", false);
+  test_is_reserved("172.16.0.0", true);
+  test_is_reserved("172.31.255.255", true);
+  test_is_reserved("172.32.0.0", false);
+  test_is_reserved("191.255.255.255", false);
+  test_is_reserved("192.0.0.0", true);
+  test_is_reserved("192.0.0.255", true);
+  test_is_reserved("192.0.1.0", false);
+  test_is_reserved("192.0.1.255", false);
+  test_is_reserved("192.0.2.0", true);
+  test_is_reserved("192.0.2.255", true);
+  test_is_reserved("192.0.3.0", false);
+  test_is_reserved("192.88.98.255", false);
+  test_is_reserved("192.88.99.0", true);
+  test_is_reserved("192.88.99.255", true);
+  test_is_reserved("192.88.100.0", false);
+  test_is_reserved("192.167.255.255", false);
+  test_is_reserved("192.168.0.0", true);
+  test_is_reserved("192.168.255.255", true);
+  test_is_reserved("192.169.0.0", false);
+  test_is_reserved("198.17.255.255", false);
+  test_is_reserved("198.18.0.0", true);
+  test_is_reserved("198.19.255.255", true);
+  test_is_reserved("198.20.0.0", false);
+  test_is_reserved("198.51.99.255", false);
+  test_is_reserved("198.51.100.0", true);
+  test_is_reserved("198.51.100.255", true);
+  test_is_reserved("198.51.101.0", false);
+  test_is_reserved("203.0.112.255", false);
+  test_is_reserved("203.0.113.0", true);
+  test_is_reserved("203.0.113.255", true);
+  test_is_reserved("203.0.114.0", false);
+  test_is_reserved("223.255.255.255", false);
+  test_is_reserved("224.0.0.0", true);
+  test_is_reserved("239.255.255.255", true);
+  test_is_reserved("240.0.0.0", true);
+  test_is_reserved("255.255.255.254", true);
+  test_is_reserved("255.255.255.255", true);
+}
+
 static void test_split(Slice str, std::pair<Slice, Slice> expected) {
   ASSERT_EQ(expected, td::split(str));
 }