diff --git a/Transmission.xcodeproj/project.pbxproj b/Transmission.xcodeproj/project.pbxproj
index 2f0ee5626..6f8b67e72 100644
--- a/Transmission.xcodeproj/project.pbxproj
+++ b/Transmission.xcodeproj/project.pbxproj
@@ -402,6 +402,7 @@
 		C809AEE7291ECFD000BFDBE1 /* NSDataAdditions.mm in Sources */ = {isa = PBXBuildFile; fileRef = C809AEE6291ECFD000BFDBE1 /* NSDataAdditions.mm */; };
 		C82B30312953337B0001BD6E /* NSDataAdditions.mm in Sources */ = {isa = PBXBuildFile; fileRef = C809AEE6291ECFD000BFDBE1 /* NSDataAdditions.mm */; };
 		C841A28129197724009F18E8 /* NSKeyedUnarchiverAdditions.mm in Sources */ = {isa = PBXBuildFile; fileRef = C841A28029197724009F18E8 /* NSKeyedUnarchiverAdditions.mm */; };
+		C843FC8429C51B9400491854 /* utils.mm in Sources */ = {isa = PBXBuildFile; fileRef = C843FC8329C51B9400491854 /* utils.mm */; };
 		C86BCD9928228A9600F45599 /* SparkleProxy.mm in Sources */ = {isa = PBXBuildFile; fileRef = C86BCD9828228A9600F45599 /* SparkleProxy.mm */; };
 		C87369652809984200573C90 /* UserNotifications.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C87369642809984200573C90 /* UserNotifications.framework */; settings = {ATTRIBUTES = (Weak, ); }; };
 		C8748D8A29891EA100D9E979 /* suffixes_dafsa.h in Headers */ = {isa = PBXBuildFile; fileRef = C8748D8929891EA100D9E979 /* suffixes_dafsa.h */; };
@@ -1207,6 +1208,7 @@
 		C81E411127F5BABD00652F56 /* CocoaCompatibility.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = CocoaCompatibility.h; sourceTree = "<group>"; };
 		C841A27F29197724009F18E8 /* NSKeyedUnarchiverAdditions.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = NSKeyedUnarchiverAdditions.h; sourceTree = "<group>"; };
 		C841A28029197724009F18E8 /* NSKeyedUnarchiverAdditions.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = NSKeyedUnarchiverAdditions.mm; sourceTree = "<group>"; };
+		C843FC8329C51B9400491854 /* utils.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = utils.mm; sourceTree = "<group>"; };
 		C86BCD9828228A9600F45599 /* SparkleProxy.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = SparkleProxy.mm; sourceTree = "<group>"; };
 		C87369642809984200573C90 /* UserNotifications.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = UserNotifications.framework; path = System/Library/Frameworks/UserNotifications.framework; sourceTree = SDKROOT; };
 		C8748D8929891EA100D9E979 /* suffixes_dafsa.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = suffixes_dafsa.h; path = "third-party/suffixes_dafsa.h"; sourceTree = SOURCE_ROOT; };
@@ -1793,6 +1795,7 @@
 				BEFC1DF30C07861A00B0BB3C /* port-forwarding-upnp.h */,
 				BEFC1DF20C07861A00B0BB3C /* utils.cc */,
 				BEFC1DF10C07861A00B0BB3C /* utils.h */,
+				C843FC8329C51B9400491854 /* utils.mm */,
 				A25BFD63167BED3B0039D1AA /* variant-benc.cc */,
 				A25BFD64167BED3B0039D1AA /* variant-common.h */,
 				A25BFD65167BED3B0039D1AA /* variant-json.cc */,
@@ -3082,6 +3085,7 @@
 				A220EC5B118C8A060022B4BE /* tr-lpd.cc in Sources */,
 				C1FEE57A1C3223CC00D62832 /* watchdir.cc in Sources */,
 				A23547E211CD0B090046EAE6 /* cache.cc in Sources */,
+				C843FC8429C51B9400491854 /* utils.mm in Sources */,
 				A284214412DA663E00FBDDBB /* tr-udp.cc in Sources */,
 				C17740D5273A002C00E455D2 /* web-utils.cc in Sources */,
 				A2679294130E00A000CB7464 /* tr-utp.cc in Sources */,
diff --git a/libtransmission/CMakeLists.txt b/libtransmission/CMakeLists.txt
index 3620805b1..6fc5d26da 100644
--- a/libtransmission/CMakeLists.txt
+++ b/libtransmission/CMakeLists.txt
@@ -150,6 +150,7 @@ target_sources(${TR_NAME}
         utils-ev.h
         utils.cc
         utils.h
+        utils.mm
         variant-benc.cc
         variant-common.h
         variant-converters.cc
@@ -198,6 +199,7 @@ tr_allow_compile_if(
         watchdir-kqueue.cc
     [=[[APPLE]]=]
         tr-assert.mm
+        utils.mm
     [=[[NOT APPLE]]=]
         tr-assert.cc
     [=[[WIN32]]=]
diff --git a/libtransmission/magnet-metainfo.h b/libtransmission/magnet-metainfo.h
index 0cbf7169d..196a391b2 100644
--- a/libtransmission/magnet-metainfo.h
+++ b/libtransmission/magnet-metainfo.h
@@ -14,6 +14,7 @@
 
 #include "announce-list.h"
 #include "tr-strbuf.h" // tr_urlbuf
+#include "utils.h" // tr_strv_convert_utf8()
 
 struct tr_error;
 struct tr_variant;
@@ -69,7 +70,7 @@ public:
 
     void setName(std::string_view name)
     {
-        name_ = name;
+        name_ = tr_strv_convert_utf8(name);
     }
 
     void addWebseed(std::string_view webseed);
diff --git a/libtransmission/torrent-metainfo.cc b/libtransmission/torrent-metainfo.cc
index fe3ca41f0..15929d180 100644
--- a/libtransmission/torrent-metainfo.cc
+++ b/libtransmission/torrent-metainfo.cc
@@ -329,11 +329,11 @@ struct MetainfoHandler final : public transmission::benc::BasicHandler<MaxBencDe
         }
         else if (pathIs(CommentKey) || pathIs(CommentUtf8Key))
         {
-            tm_.comment_ = tr_strv_replace_invalid(value);
+            tm_.comment_ = tr_strv_convert_utf8(value);
         }
         else if (pathIs(CreatedByKey) || pathIs(CreatedByUtf8Key))
         {
-            tm_.creator_ = tr_strv_replace_invalid(value);
+            tm_.creator_ = tr_strv_convert_utf8(value);
         }
         else if (
             pathIs(SourceKey) || pathIs(InfoKey, SourceKey) || //
@@ -344,7 +344,7 @@ struct MetainfoHandler final : public transmission::benc::BasicHandler<MaxBencDe
             // to have the same use as the 'source' key
             // http://wiki.bitcomet.com/inside_bitcomet
 
-            tm_.source_ = tr_strv_replace_invalid(value);
+            tm_.source_ = tr_strv_convert_utf8(value);
         }
         else if (pathIs(AnnounceKey))
         {
@@ -360,7 +360,7 @@ struct MetainfoHandler final : public transmission::benc::BasicHandler<MaxBencDe
         }
         else if (pathIs(InfoKey, NameKey) || pathIs(InfoKey, NameUtf8Key))
         {
-            tm_.name_ = tr_strv_replace_invalid(value);
+            tm_.setName(value);
         }
         else if (pathIs(InfoKey, PiecesKey))
         {
@@ -393,7 +393,7 @@ struct MetainfoHandler final : public transmission::benc::BasicHandler<MaxBencDe
         else if (pathIs(MagnetInfoKey, DisplayNameKey))
         {
             // compatibility with Transmission <= 3.0
-            tm_.name_ = tr_strv_replace_invalid(value);
+            tm_.setName(value);
         }
         else if (pathIs(MagnetInfoKey, InfoHashKey))
         {
diff --git a/libtransmission/utils.cc b/libtransmission/utils.cc
index 1927496a3..9ce9f88bc 100644
--- a/libtransmission/utils.cc
+++ b/libtransmission/utils.cc
@@ -268,9 +268,24 @@ double tr_getRatio(uint64_t numerator, uint64_t denominator)
 
 // ---
 
+#ifndef __APPLE__
+
+std::string tr_strv_convert_utf8(std::string_view sv)
+{
+    return tr_strv_replace_invalid(sv);
+}
+
+#endif
+
 std::string tr_strv_replace_invalid(std::string_view sv, uint32_t replacement)
 {
+    // stripping characters after first \0
+    if (auto first_null = sv.find('\0'); first_null != std::string::npos)
+    {
+        sv = { std::data(sv), first_null };
+    }
     auto out = std::string{};
+    out.reserve(std::size(sv));
     utf8::unchecked::replace_invalid(std::data(sv), std::data(sv) + std::size(sv), std::back_inserter(out), replacement);
     return out;
 }
diff --git a/libtransmission/utils.h b/libtransmission/utils.h
index c15dfc341..f49d98ef0 100644
--- a/libtransmission/utils.h
+++ b/libtransmission/utils.h
@@ -204,6 +204,8 @@ constexpr bool tr_strvSep(std::string_view* sv, std::string_view* token, char de
 
 [[nodiscard]] std::string_view tr_strvStrip(std::string_view str);
 
+[[nodiscard]] std::string tr_strv_convert_utf8(std::string_view sv);
+
 [[nodiscard]] std::string tr_strv_replace_invalid(std::string_view sv, uint32_t replacement = 0xFFFD /*�*/);
 
 /**
diff --git a/libtransmission/utils.mm b/libtransmission/utils.mm
new file mode 100644
index 000000000..125a5b0c0
--- /dev/null
+++ b/libtransmission/utils.mm
@@ -0,0 +1,49 @@
+// This file Copyright © 2022-2023 Mnemosyne LLC.
+// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
+// or any future license endorsed by Mnemosyne LLC.
+// License text can be found in the licenses/ folder.
+
+#import <Foundation/Foundation.h>
+
+#include <string>
+#include <string_view>
+
+#include "utils.h"
+
+// macOS implementation of tr_strv_convert_utf8() that autodetects the encoding.
+// This replaces the generic implementation of the function in utils.cc.
+
+std::string tr_strv_convert_utf8(std::string_view sv)
+{
+    // UTF-8 encoding
+    char const* validUTF8 = [[NSString alloc] initWithBytes:std::data(sv) length:std::size(sv) encoding:NSUTF8StringEncoding].UTF8String;
+    if (validUTF8)
+    {
+        return std::string(validUTF8);
+    }
+
+    // autodetection of the encoding (#3434)
+    NSString* convertedString;
+    NSStringEncoding stringEncoding = [NSString
+        stringEncodingForData:[NSData dataWithBytes:std::data(sv) length:std::size(sv)]
+              encodingOptions:@{
+                  // We disallow lossy conversion, and will leave it to `utf8::unchecked::replace_invalid`.
+                  NSStringEncodingDetectionAllowLossyKey : @NO,
+                  // We only set the likely language.
+                  // If we were to set suggested encodings, then whatever is listed first would take precedence on all others, making for instance kCFStringEncodingDOSJapanese (cp932) and kCFStringEncodingDOSRussian (cp866) taking priority on each other.
+                  NSStringEncodingDetectionLikelyLanguageKey : NSLocale.currentLocale.languageCode
+              }
+              convertedString:&convertedString
+          usedLossyConversion:nil];
+    if (stringEncoding)
+    {
+        validUTF8 = convertedString.UTF8String;
+        if (validUTF8)
+        {
+            return std::string(validUTF8);
+        }
+    }
+
+    // invalid encoding
+    return tr_strv_replace_invalid(sv);
+}
diff --git a/tests/libtransmission/utils-test.cc b/tests/libtransmission/utils-test.cc
index 1f7097f33..ae13eb1af 100644
--- a/tests/libtransmission/utils-test.cc
+++ b/tests/libtransmission/utils-test.cc
@@ -151,15 +151,15 @@ TEST_F(UtilsTest, strvReplaceInvalid)
     EXPECT_EQ(out, tr_strv_replace_invalid(out));
 }
 
-TEST_F(UtilsTest, strvReplaceInvalidFuzz)
+TEST_F(UtilsTest, strvConvertUtf8Fuzz)
 {
     auto buf = std::vector<char>{};
     for (size_t i = 0; i < 1000; ++i)
     {
         buf.resize(tr_rand_int(4096U));
         tr_rand_buffer(std::data(buf), std::size(buf));
-        auto const out = tr_strv_replace_invalid({ std::data(buf), std::size(buf) });
-        EXPECT_EQ(out, tr_strv_replace_invalid(out));
+        auto const out = tr_strv_convert_utf8({ std::data(buf), std::size(buf) });
+        EXPECT_EQ(out, tr_strv_convert_utf8(out));
     }
 }