diff --git a/td/telegram/SecretChatActor.h b/td/telegram/SecretChatActor.h
index afae8dc6d..34224a2da 100644
--- a/td/telegram/SecretChatActor.h
+++ b/td/telegram/SecretChatActor.h
@@ -496,7 +496,7 @@ class SecretChatActor final : public NetQueryCallback {
    public:
     Change() : message_id() {
     }
-    explicit operator bool() const {
+    explicit operator bool() const noexcept {
       return !data.empty();
     }
     explicit Change(const StateT &state) {
diff --git a/td/telegram/files/FileManager.cpp b/td/telegram/files/FileManager.cpp
index 4aae985f9..98ae3451a 100644
--- a/td/telegram/files/FileManager.cpp
+++ b/td/telegram/files/FileManager.cpp
@@ -145,7 +145,7 @@ FileNode *FileNodePtr::get_unsafe() const {
   return file_manager_->get_file_node_raw(file_id_);
 }
 
-FileNodePtr::operator bool() const {
+FileNodePtr::operator bool() const noexcept {
   return file_manager_ != nullptr && get_unsafe() != nullptr;
 }
 
diff --git a/td/telegram/files/FileManager.h b/td/telegram/files/FileManager.h
index 1572b609c..fa8008635 100644
--- a/td/telegram/files/FileManager.h
+++ b/td/telegram/files/FileManager.h
@@ -208,7 +208,7 @@ class FileNodePtr {
   FileNode &operator*() const;
   FileNode *get() const;
   FullRemoteFileLocation *get_remote() const;
-  explicit operator bool() const;
+  explicit operator bool() const noexcept;
 
  private:
   FileId file_id_;
@@ -229,7 +229,7 @@ class ConstFileNodePtr {
     return file_node_ptr_.operator*();
   }
 
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return static_cast<bool>(file_node_ptr_);
   }
   const FullRemoteFileLocation *get_remote() const {
diff --git a/td/telegram/net/NetQueryCounter.h b/td/telegram/net/NetQueryCounter.h
index a6abc533c..744245b0e 100644
--- a/td/telegram/net/NetQueryCounter.h
+++ b/td/telegram/net/NetQueryCounter.h
@@ -24,7 +24,7 @@ class NetQueryCounter {
     counter->fetch_add(1, std::memory_order_relaxed);
   }
 
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return static_cast<bool>(ptr_);
   }
 
diff --git a/tdnet/td/net/SslStream.h b/tdnet/td/net/SslStream.h
index cbdbe5783..4af0da30e 100644
--- a/tdnet/td/net/SslStream.h
+++ b/tdnet/td/net/SslStream.h
@@ -34,7 +34,7 @@ class SslStream {
   size_t flow_read(MutableSlice slice);
   size_t flow_write(Slice slice);
 
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return static_cast<bool>(impl_);
   }
 
diff --git a/tdutils/td/utils/CancellationToken.h b/tdutils/td/utils/CancellationToken.h
index 729a94621..19f280655 100644
--- a/tdutils/td/utils/CancellationToken.h
+++ b/tdutils/td/utils/CancellationToken.h
@@ -19,7 +19,7 @@ struct RawCancellationToken {
 
 class CancellationToken {
  public:
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     // empty CancellationToken is never canceled
     if (!token_) {
       return false;
diff --git a/tdutils/td/utils/FlatHashMapChunks.h b/tdutils/td/utils/FlatHashMapChunks.h
index 70fc36bac..86aaa49f3 100644
--- a/tdutils/td/utils/FlatHashMapChunks.h
+++ b/tdutils/td/utils/FlatHashMapChunks.h
@@ -36,7 +36,7 @@ namespace td {
 template <int shift>
 struct MaskIterator {
   uint64 mask;
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return mask != 0;
   }
   int pos() const {
diff --git a/tdutils/td/utils/MpscLinkQueue.h b/tdutils/td/utils/MpscLinkQueue.h
index de2bff9f4..a1b05c279 100644
--- a/tdutils/td/utils/MpscLinkQueue.h
+++ b/tdutils/td/utils/MpscLinkQueue.h
@@ -158,7 +158,7 @@ class MpscLinkQueueUniquePtrNode {
     return MpscLinkQueueUniquePtrNode<Value>(unique_ptr<Value>(Value::from_mpsc_link_queue_node(node)));
   }
 
-  explicit operator bool() {
+  explicit operator bool() const noexcept {
     return ptr_ != nullptr;
   }
 
diff --git a/tdutils/td/utils/Promise.h b/tdutils/td/utils/Promise.h
index 1ba653094..4e83045d6 100644
--- a/tdutils/td/utils/Promise.h
+++ b/tdutils/td/utils/Promise.h
@@ -245,7 +245,7 @@ class Promise {
   Promise(F &&f) : promise_(detail::promise_interface_ptr<T>(std::forward<F>(f))) {
   }
 
-  explicit operator bool() {
+  explicit operator bool() const noexcept {
     return static_cast<bool>(promise_);
   }
 
diff --git a/tdutils/td/utils/SharedObjectPool.h b/tdutils/td/utils/SharedObjectPool.h
index 36e2c6cca..850c14aa2 100644
--- a/tdutils/td/utils/SharedObjectPool.h
+++ b/tdutils/td/utils/SharedObjectPool.h
@@ -123,10 +123,10 @@ class SharedPtr {
     other.raw_ = nullptr;
     return *this;
   }
-  bool empty() const {
+  bool empty() const noexcept {
     return raw_ == nullptr;
   }
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return !empty();
   }
   uint64 use_cnt() const {
@@ -255,7 +255,7 @@ class SharedObjectPool {
     Raw *get() const {
       return raw_;
     }
-    explicit operator bool() const {
+    explicit operator bool() noexcept {
       return raw_ != nullptr;
     }
 
diff --git a/tdutils/td/utils/Time.h b/tdutils/td/utils/Time.h
index bf1dce6e1..4149c93d9 100644
--- a/tdutils/td/utils/Time.h
+++ b/tdutils/td/utils/Time.h
@@ -69,7 +69,7 @@ class Timestamp {
     return is_in_past(now_cached());
   }
 
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return at_ > 0;
   }
 
diff --git a/tdutils/td/utils/optional.h b/tdutils/td/utils/optional.h
index 228ceee58..579127f62 100644
--- a/tdutils/td/utils/optional.h
+++ b/tdutils/td/utils/optional.h
@@ -46,7 +46,7 @@ class optional {
   optional &operator=(optional &&other) = default;
   ~optional() = default;
 
-  explicit operator bool() const {
+  explicit operator bool() const noexcept {
     return impl_.is_ok();
   }
   T &value() {
diff --git a/tdutils/td/utils/port/detail/NativeFd.cpp b/tdutils/td/utils/port/detail/NativeFd.cpp
index 0de8c9c1c..7a492857e 100644
--- a/tdutils/td/utils/port/detail/NativeFd.cpp
+++ b/tdutils/td/utils/port/detail/NativeFd.cpp
@@ -156,7 +156,7 @@ NativeFd::~NativeFd() {
   close();
 }
 
-NativeFd::operator bool() const {
+NativeFd::operator bool() const noexcept {
   return fd_ != empty_fd();
 }
 
diff --git a/tdutils/td/utils/port/detail/NativeFd.h b/tdutils/td/utils/port/detail/NativeFd.h
index 690590fe3..ac4bddccf 100644
--- a/tdutils/td/utils/port/detail/NativeFd.h
+++ b/tdutils/td/utils/port/detail/NativeFd.h
@@ -38,7 +38,7 @@ class NativeFd {
   NativeFd &operator=(NativeFd &&other) noexcept;
   ~NativeFd();
 
-  explicit operator bool() const;
+  explicit operator bool() const noexcept;
 
   Fd fd() const;
   Socket socket() const;