diff --git a/Source/Core/Common/GekkoDisassembler.cpp b/Source/Core/Common/GekkoDisassembler.cpp
diff --git a/Source/Core/Common/GekkoDisassembler.h b/Source/Core/Common/GekkoDisassembler.h
@@ -93,42 +93,6 @@ class GekkoDisassembler final
 
   static u32* DoDisassembly(bool big_endian);
 
-  static u32 HelperRotateMask(int r, int mb, int me)
-  {
-    // first make 001111111111111 part
-    unsigned int begin = 0xFFFFFFFF >> mb;
-    // then make 000000000001111 part, which is used to flip the bits of the first one
-    unsigned int end = me < 31 ? (0xFFFFFFFF >> (me + 1)) : 0;
-    // do the bitflip
-    unsigned int mask = begin ^ end;
-    // and invert if backwards
-    if (me < mb)
-      mask = ~mask;
-    // rotate the mask so it can be applied to source reg
-    // return _rotl(mask, 32 - r);
-    return (mask << (32 - r)) | (mask >> r);
-  }
-
-  static std::string ldst_offs(u32 val)
-  {
-    if (val == 0)
-    {
-      return "0";
-    }
-    else
-    {
-      if (val & 0x8000)
-      {
-        return StringFromFormat("-0x%.4X", ((~val) & 0xffff) + 1);
-      }
-      else
-      {
-        return StringFromFormat("0x%.4X", val);
-      }
-    }
-  }
-
-  static int SEX12(u32 x) { return x & 0x800 ? (x | 0xFFFFF000) : x; }
   enum InstructionType
   {
     PPCINSTR_OTHER = 0,   // No additional info for other instr.

diff --git a/Source/Core/Common/JitRegister.cpp b/Source/Core/Common/JitRegister.cpp
@@ -2,16 +2,18 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
-#include <cinttypes>
+#include "Common/JitRegister.h"
+
 #include <cstddef>
 #include <cstdio>
 #include <cstdlib>
 #include <fstream>
 #include <string>
 
+#include <fmt/format.h>
+
 #include "Common/CommonTypes.h"
 #include "Common/File.h"
-#include "Common/JitRegister.h"
 #include "Common/StringUtil.h"
 
 #ifdef _WIN32
@@ -48,8 +50,8 @@ void Init(const std::string& perf_dir)
 
   if (!perf_dir.empty() || getenv("PERF_BUILDID_DIR"))
   {
-    std::string dir = perf_dir.empty() ? "/tmp" : perf_dir;
-    std::string filename = StringFromFormat("%s/perf-%d.map", dir.data(), getpid());
+    const std::string dir = perf_dir.empty() ? "/tmp" : perf_dir;
+    const std::string filename = fmt::format("{}/perf-{}.map", dir, getpid());
     s_perf_map_file.Open(filename, "w");
     // Disable buffering in order to avoid missing some mappings
     // if the event of a crash:
@@ -90,24 +92,23 @@ void RegisterV(const void* base_address, u32 code_size, const char* format, va_l
   std::string symbol_name = StringFromFormatV(format, args);
 
 #if defined USE_OPROFILE && USE_OPROFILE
-  op_write_native_code(s_agent, symbol_name.data(), (u64)base_address, base_address, code_size);
+  op_write_native_code(s_agent, symbol_name.c_str(), (u64)base_address, base_address, code_size);
 #endif
 
 #ifdef USE_VTUNE
   iJIT_Method_Load jmethod = {0};
   jmethod.method_id = iJIT_GetNewMethodID();
   jmethod.method_load_address = const_cast<void*>(base_address);
   jmethod.method_size = code_size;
-  jmethod.method_name = const_cast<char*>(symbol_name.data());
+  jmethod.method_name = const_cast<char*>(symbol_name.c_str());
   iJIT_NotifyEvent(iJVM_EVENT_TYPE_METHOD_LOAD_FINISHED, (void*)&jmethod);
 #endif
 
   // Linux perf /tmp/perf-$pid.map:
-  if (s_perf_map_file.IsOpen())
-  {
-    std::string entry =
-        StringFromFormat("%" PRIx64 " %x %s\n", (u64)base_address, code_size, symbol_name.data());
-    s_perf_map_file.WriteBytes(entry.data(), entry.size());
-  }
+  if (!s_perf_map_file.IsOpen())
+    return;
+
+  const auto entry = fmt::format("{} {:x} {}\n", fmt::ptr(base_address), code_size, symbol_name);
+  s_perf_map_file.WriteBytes(entry.data(), entry.size());
 }
 }  // namespace JitRegister
diff --git a/Source/Core/Common/Logging/LogManager.cpp b/Source/Core/Common/Logging/LogManager.cpp
@@ -2,6 +2,8 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
+#include "Common/Logging/LogManager.h"
+
 #include <algorithm>
 #include <cstdarg>
 #include <cstring>
@@ -10,12 +12,13 @@
 #include <ostream>
 #include <string>
 
+#include <fmt/format.h>
+
 #include "Common/CommonPaths.h"
 #include "Common/Config/Config.h"
 #include "Common/FileUtil.h"
 #include "Common/Logging/ConsoleListener.h"
 #include "Common/Logging/Log.h"
-#include "Common/Logging/LogManager.h"
 #include "Common/StringUtil.h"
 #include "Common/Timer.h"
 
@@ -207,9 +210,9 @@ void LogManager::LogWithFullPath(LogTypes::LOG_LEVELS level, LogTypes::LOG_TYPE
   char temp[MAX_MSGLEN];
   CharArrayFromFormatV(temp, MAX_MSGLEN, format, args);
 
-  std::string msg =
-      StringFromFormat("%s %s:%u %c[%s]: %s\n", Common::Timer::GetTimeFormatted().c_str(), file,
-                       line, LogTypes::LOG_LEVEL_TO_CHAR[(int)level], GetShortName(type), temp);
+  const std::string msg =
+      fmt::format("{} {}:{} {}[{}]: {}\n", Common::Timer::GetTimeFormatted(), file, line,
+                  LogTypes::LOG_LEVEL_TO_CHAR[(int)level], GetShortName(type), temp);
 
   for (auto listener_id : m_listener_ids)
     if (m_listeners[listener_id])

diff --git a/Source/Core/Common/MD5.cpp b/Source/Core/Common/MD5.cpp
@@ -2,12 +2,15 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
+#include "Common/MD5.h"
+
 #include <fstream>
 #include <functional>
 #include <mbedtls/md5.h>
 #include <string>
 
-#include "Common/MD5.h"
+#include <fmt/format.h>
+
 #include "Common/StringUtil.h"
 #include "DiscIO/Blob.h"
 
@@ -45,7 +48,7 @@ std::string MD5Sum(const std::string& file_path, std::function<bool(int)> report
 
   // Convert to hex
   for (u8 n : output)
-    output_string += StringFromFormat("%02x", n);
+    output_string += fmt::format("{:02x}", n);
 
   return output_string;
 }

diff --git a/Source/Core/Common/NandPaths.cpp b/Source/Core/Common/NandPaths.cpp
@@ -9,6 +9,8 @@
 #include <unordered_set>
 #include <vector>
 
+#include <fmt/format.h>
+
 #include "Common/CommonTypes.h"
 #include "Common/FileUtil.h"
 #include "Common/StringUtil.h"
@@ -28,21 +30,20 @@ static std::string RootUserPath(std::optional<FromWhichRoot> from)
 
 std::string GetImportTitlePath(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return RootUserPath(from) + StringFromFormat("/import/%08x/%08x",
-                                               static_cast<u32>(title_id >> 32),
-                                               static_cast<u32>(title_id));
+  return RootUserPath(from) + fmt::format("/import/{:08x}/{:08x}", static_cast<u32>(title_id >> 32),
+                                          static_cast<u32>(title_id));
 }
 
 std::string GetTicketFileName(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return StringFromFormat("%s/ticket/%08x/%08x.tik", RootUserPath(from).c_str(),
-                          static_cast<u32>(title_id >> 32), static_cast<u32>(title_id));
+  return fmt::format("{}/ticket/{:08x}/{:08x}.tik", RootUserPath(from),
+                     static_cast<u32>(title_id >> 32), static_cast<u32>(title_id));
 }
 
 std::string GetTitlePath(u64 title_id, std::optional<FromWhichRoot> from)
 {
-  return StringFromFormat("%s/title/%08x/%08x", RootUserPath(from).c_str(),
-                          static_cast<u32>(title_id >> 32), static_cast<u32>(title_id));
+  return fmt::format("{}/title/{:08x}/{:08x}", RootUserPath(from), static_cast<u32>(title_id >> 32),
+                     static_cast<u32>(title_id));
 }
 
 std::string GetTitleDataPath(u64 title_id, std::optional<FromWhichRoot> from)
@@ -62,7 +63,7 @@ std::string GetTMDFileName(u64 title_id, std::optional<FromWhichRoot> from)
 
 std::string GetMiiDatabasePath(std::optional<FromWhichRoot> from)
 {
-  return StringFromFormat("%s/shared2/menu/FaceLib/RFL_DB.dat", RootUserPath(from).c_str());
+  return fmt::format("{}/shared2/menu/FaceLib/RFL_DB.dat", RootUserPath(from));
 }
 
 bool IsTitlePath(const std::string& path, std::optional<FromWhichRoot> from, u64* title_id)
@@ -111,7 +112,7 @@ std::string EscapeFileName(const std::string& filename)
   for (char c : filename_with_escaped_double_underscores)
   {
     if ((c >= 0 && c <= 0x1F) || chars_to_replace.find(c) != chars_to_replace.end())
-      result.append(StringFromFormat("__%02x__", c));
+      result.append(fmt::format("__{:02x}__", c));
     else
       result.push_back(c);
   }

diff --git a/Source/Core/Common/Network.cpp b/Source/Core/Common/Network.cpp
@@ -9,8 +9,9 @@
 #include <cstring>
 #include <ctime>
 
+#include <fmt/format.h>
+
 #include "Common/Random.h"
-#include "Common/StringUtil.h"
 
 namespace Common
 {
@@ -38,8 +39,8 @@ MACAddress GenerateMacAddress(const MACConsumer type)
 
 std::string MacAddressToString(const MACAddress& mac)
 {
-  return StringFromFormat("%02x:%02x:%02x:%02x:%02x:%02x", mac[0], mac[1], mac[2], mac[3], mac[4],
-                          mac[5]);
+  return fmt::format("{:02x}:{:02x}:{:02x}:{:02x}:{:02x}:{:02x}", mac[0], mac[1], mac[2], mac[3],
+                     mac[4], mac[5]);
 }
 
 std::optional<MACAddress> StringToMacAddress(const std::string& mac_string)

diff --git a/Source/Core/Common/StringUtil.cpp b/Source/Core/Common/StringUtil.cpp
@@ -2,8 +2,9 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
+#include "Common/StringUtil.h"
+
 #include <algorithm>
-#include <cinttypes>
 #include <cstdarg>
 #include <cstddef>
 #include <cstdio>
@@ -18,11 +19,12 @@
 #include <string>
 #include <vector>
 
+#include <fmt/format.h>
+
 #include "Common/CommonFuncs.h"
 #include "Common/CommonPaths.h"
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
-#include "Common/StringUtil.h"
 #include "Common/Swap.h"
 
 #ifdef _WIN32
@@ -51,12 +53,12 @@ std::string HexDump(const u8* data, size_t size)
   std::string out;
   for (size_t row_start = 0; row_start < size; row_start += BYTES_PER_LINE)
   {
-    out += StringFromFormat("%06zx: ", row_start);
+    out += fmt::format("{:06x}: ", row_start);
     for (size_t i = 0; i < BYTES_PER_LINE; ++i)
     {
       if (row_start + i < size)
       {
-        out += StringFromFormat("%02hhx ", data[row_start + i]);
+        out += fmt::format("{:02x} ", data[row_start + i]);
       }
       else
       {
@@ -294,27 +296,27 @@ bool TryParse(const std::string& str, bool* const output)
 
 std::string ValueToString(u16 value)
 {
-  return StringFromFormat("0x%04x", value);
+  return fmt::format("0x{:04x}", value);
 }
 
 std::string ValueToString(u32 value)
 {
-  return StringFromFormat("0x%08x", value);
+  return fmt::format("0x{:08x}", value);
 }
 
 std::string ValueToString(u64 value)
 {
-  return StringFromFormat("0x%016" PRIx64, value);
+  return fmt::format("0x{:016x}", value);
 }
 
 std::string ValueToString(float value)
 {
-  return StringFromFormat("%#.9g", value);
+  return fmt::format("{:#.9g}", value);
 }
 
 std::string ValueToString(double value)
 {
-  return StringFromFormat("%#.17g", value);
+  return fmt::format("{:#.17g}", value);
 }
 
 std::string ValueToString(int value)
@@ -324,7 +326,7 @@ std::string ValueToString(int value)
 
 std::string ValueToString(s64 value)
 {
-  return StringFromFormat("%" PRId64, value);
+  return std::to_string(value);
 }
 
 std::string ValueToString(bool value)

diff --git a/Source/Core/Common/Timer.cpp b/Source/Core/Common/Timer.cpp
@@ -2,7 +2,8 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
-#include <cinttypes>
+#include "Common/Timer.h"
+
 #include <ctime>
 #include <string>
 
@@ -16,9 +17,10 @@
 #include <sys/time.h>
 #endif
 
+#include <fmt/format.h>
+
 #include "Common/CommonTypes.h"
 #include "Common/StringUtil.h"
-#include "Common/Timer.h"
 
 namespace Common
 {
@@ -149,9 +151,8 @@ std::string Timer::GetTimeElapsedFormatted() const
   // Hours
   u32 Hours = Minutes / 60;
 
-  std::string TmpStr = StringFromFormat("%02i:%02i:%02i:%03" PRIu64, Hours, Minutes % 60,
-                                        Seconds % 60, Milliseconds % 1000);
-  return TmpStr;
+  return fmt::format("{:02}:{:02}:{:02}:{:03}", Hours, Minutes % 60, Seconds % 60,
+                     Milliseconds % 1000);
 }
 
 // Get current time
@@ -217,15 +218,15 @@ std::string Timer::GetTimeFormatted()
 #ifdef _WIN32
   struct timeb tp;
   (void)::ftime(&tp);
-  return UTF16ToUTF8(tmp) + StringFromFormat(":%03i", tp.millitm);
+  return UTF16ToUTF8(tmp) + fmt::format(":{:03}", tp.millitm);
 #elif defined __APPLE__
   struct timeval t;
   (void)gettimeofday(&t, nullptr);
-  return StringFromFormat("%s:%03d", tmp, (int)(t.tv_usec / 1000));
+  return fmt::format("{}:{:03}", tmp, t.tv_usec / 1000);
 #else
   struct timespec t;
   (void)clock_gettime(CLOCK_MONOTONIC, &t);
-  return StringFromFormat("%s:%03d", tmp, (int)(t.tv_nsec / 1000000));
+  return fmt::format("{}:{:03}", tmp, t.tv_nsec / 1000000);
 #endif
 }
 

diff --git a/Source/VSProps/Base.props b/Source/VSProps/Base.props
@@ -41,6 +41,7 @@
       <AdditionalIncludeDirectories>$(ExternalsDir)curl\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ExternalsDir)enet\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ExternalsDir)ffmpeg\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <AdditionalIncludeDirectories>$(ExternalsDir)fmt\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ExternalsDir)GL;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ExternalsDir)glslang\glslang\Public;$(ExternalsDir)glslang\SPIRV;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ExternalsDir)imgui;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
@@ -55,6 +56,7 @@
       <AdditionalIncludeDirectories>$(ExternalsDir)xxhash;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ExternalsDir)zlib;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>HAVE_FFMPEG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>FMT_HEADER_ONLY=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions>_CRT_SECURE_NO_WARNINGS;_CRT_SECURE_NO_DEPRECATE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions>USE_UPNP;USE_USBDK;__LIBUSB__;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions>_M_X86=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>