diff --git a/imgui.cpp b/imgui.cpp
index bcd4daf7..2e7ceb6d 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -1351,6 +1351,11 @@ void ImStrTrimBlanks(char* buf)
 // B) When buf==NULL vsnprintf() will return the output size.
 #ifndef IMGUI_DISABLE_FORMAT_STRING_FUNCTIONS
 
+#ifdef IMGUI_USE_STB_SPRINTF
+#define STB_SPRINTF_IMPLEMENTATION
+#include "imstb_sprintf.h"
+#endif
+
 #if defined(_MSC_VER) && !defined(vsnprintf)
 #define vsnprintf _vsnprintf
 #endif
@@ -1359,7 +1364,11 @@ int ImFormatString(char* buf, size_t buf_size, const char* fmt, ...)
 {
     va_list args;
     va_start(args, fmt);
+#ifdef IMGUI_USE_STB_SPRINTF
+    int w = stbsp_vsnprintf(buf, (int)buf_size, fmt, args);
+#else
     int w = vsnprintf(buf, buf_size, fmt, args);
+#endif
     va_end(args);
     if (buf == NULL)
         return w;
@@ -1371,7 +1380,11 @@ int ImFormatString(char* buf, size_t buf_size, const char* fmt, ...)
 
 int ImFormatStringV(char* buf, size_t buf_size, const char* fmt, va_list args)
 {
+#ifdef IMGUI_USE_STB_SPRINTF
+    int w = stbsp_vsnprintf(buf, (int)buf_size, fmt, args);
+#else
     int w = vsnprintf(buf, buf_size, fmt, args);
+#endif
     if (buf == NULL)
         return w;
     if (w == -1 || w >= (int)buf_size)