diff --git a/src/packet_buffer.cpp b/src/packet_buffer.cpp
index e2112b2f9..275b4ffe6 100644
--- a/src/packet_buffer.cpp
+++ b/src/packet_buffer.cpp
@@ -45,11 +45,11 @@ namespace libtorrent {
 	void packet_buffer::check_invariant() const
 	{
 		int count = 0;
-		for (int i = 0; i < int(m_capacity); ++i)
+		for (int i = 0; i < m_capacity; ++i)
 		{
 			count += m_storage[i] ? 1 : 0;
 		}
-		TORRENT_ASSERT(count == int(m_size));
+		TORRENT_ASSERT(count == m_size);
 	}
 #endif
 
@@ -192,4 +192,3 @@ namespace libtorrent {
 		return old_value;
 	}
 }
-
diff --git a/src/session_impl.cpp b/src/session_impl.cpp
index 1d86372c5..9f1ed768d 100644
--- a/src/session_impl.cpp
+++ b/src/session_impl.cpp
@@ -2618,7 +2618,7 @@ namespace aux {
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		// add the current time to the PRNG, to add more unpredictability
-		std::uint64_t now = clock_type::now().time_since_epoch().count();
+		std::int64_t now = clock_type::now().time_since_epoch().count();
 		// assume 12 bits of entropy (i.e. about 8 milliseconds)
 		RAND_add(&now, 8, 1.5);
 #ifdef TORRENT_MACOS_DEPRECATED_LIBCRYPTO
diff --git a/src/torrent.cpp b/src/torrent.cpp
index df92d97e7..2fd98f9bd 100644
--- a/src/torrent.cpp
+++ b/src/torrent.cpp
@@ -1421,14 +1421,14 @@ namespace libtorrent
 			ASN1_IA5STRING* domain = gen->d.dNSName;
 			if (domain->type != V_ASN1_IA5STRING || !domain->data || !domain->length) continue;
 			const char* torrent_name = reinterpret_cast<const char*>(domain->data);
-			std::size_t name_length = domain->length;
+			std::size_t name_length = aux::numeric_cast<std::size_t>(domain->length);
 
 #ifndef TORRENT_DISABLE_LOGGING
 			if (i > 1) names += " | n: ";
 			names.append(torrent_name, name_length);
 #endif
-			if (strncmp(torrent_name, "*", name_length) == 0
-				|| strncmp(torrent_name, m_torrent_file->name().c_str(), name_length) == 0)
+			if (std::strncmp(torrent_name, "*", name_length) == 0
+				|| std::strncmp(torrent_name, m_torrent_file->name().c_str(), name_length) == 0)
 			{
 #ifndef TORRENT_DISABLE_LOGGING
 				match = true;
@@ -1454,7 +1454,7 @@ namespace libtorrent
 		if (common_name && common_name->data && common_name->length)
 		{
 			const char* torrent_name = reinterpret_cast<const char*>(common_name->data);
-			std::size_t name_length = common_name->length;
+			std::size_t name_length = aux::numeric_cast<std::size_t>(common_name->length);
 
 #ifndef TORRENT_DISABLE_LOGGING
 			if (!names.empty()) names += " | n: ";
@@ -1488,7 +1488,7 @@ namespace libtorrent
 		// this is needed for openssl < 1.0 to decrypt keys created by openssl 1.0+
 		OpenSSL_add_all_algorithms();
 
-		std::uint64_t const now = clock_type::now().time_since_epoch().count();
+		std::int64_t const now = clock_type::now().time_since_epoch().count();
 		// assume 9 bits of entropy (i.e. about 1 millisecond)
 		RAND_add(&now, 8, 1.125);
 		RAND_add(&info_hash()[0], 20, 3);
diff --git a/src/utp_stream.cpp b/src/utp_stream.cpp
index f9cf8f0e5..5d2377b14 100644
--- a/src/utp_stream.cpp
+++ b/src/utp_stream.cpp
@@ -299,7 +299,7 @@ struct utp_socket_impl
 	bool consume_incoming_data(
 		utp_header const* ph, std::uint8_t const* ptr, int payload_size, time_point now);
 	void update_mtu_limits();
-	void experienced_loss(int seq_nr);
+	void experienced_loss(std::uint32_t seq_nr);
 
 	void set_state(int s);
 
@@ -1439,7 +1439,7 @@ std::pair<std::uint32_t, int> utp_socket_impl::parse_sack(std::uint16_t const pa
 	if (size == 0) return { 0u, 0 };
 
 	// this is the sequence number the current bit represents
-	int ack_nr = (packet_ack + 2) & ACK_MASK;
+	std::uint32_t ack_nr = (packet_ack + 2) & ACK_MASK;
 
 #if TORRENT_VERBOSE_UTP_LOG
 	std::string bitmask;
@@ -1464,7 +1464,7 @@ std::pair<std::uint32_t, int> utp_socket_impl::parse_sack(std::uint16_t const pa
 	int dups = 0;
 
 	// the sequence number of the last ACKed packet
-	int last_ack = packet_ack;
+	std::uint32_t last_ack = packet_ack;
 
 	int acked_bytes = 0;
 	std::uint32_t min_rtt = std::numeric_limits<std::uint32_t>::max();
@@ -2181,7 +2181,7 @@ bool utp_socket_impl::resend_packet(packet* p, bool fast_resend)
 	return !m_stalled;
 }
 
-void utp_socket_impl::experienced_loss(int const seq_nr)
+void utp_socket_impl::experienced_loss(std::uint32_t const seq_nr)
 {
 	INVARIANT_CHECK;
 
@@ -2828,7 +2828,7 @@ bool utp_socket_impl::incoming_packet(span<std::uint8_t const> buf
 	int const size = int(buf.size());
 	ptr += sizeof(utp_header);
 
-	unsigned int extension = ph->extension;
+	std::uint8_t extension = ph->extension;
 	while (extension)
 	{
 		// invalid packet. It says it has an extension header
@@ -2839,7 +2839,7 @@ bool utp_socket_impl::incoming_packet(span<std::uint8_t const> buf
 			m_sm.inc_stats_counter(counters::utp_invalid_pkts_in);
 			return true;
 		}
-		int next_extension = *ptr++;
+		std::uint8_t const next_extension = *ptr++;
 		int len = *ptr++;
 		if (len < 0)
 		{
@@ -2848,7 +2848,7 @@ bool utp_socket_impl::incoming_packet(span<std::uint8_t const> buf
 			m_sm.inc_stats_counter(counters::utp_invalid_pkts_in);
 			return true;
 		}
-		if (ptr - buf.data() + len > ptrdiff_t(size))
+		if (ptr - buf.data() + len > size)
 		{
 			UTP_LOG("%8p: ERROR: invalid extension header size:%d packet:%d\n"
 				, static_cast<void*>(this), len, int(ptr - buf.data()));