diff --git a/include/platform.hpp b/include/platform.hpp
index bbee456e..d899ae06 100644
--- a/include/platform.hpp
+++ b/include/platform.hpp
@@ -67,6 +67,13 @@
 	#define setmode(fd, mode) (0)
 #endif
 
+// Windows has 32-bit `long`, which limits `fseek` and `ftell` to 2 GiB
+#if defined(_MSC_VER) || defined(__MINGW32__)
+	#include <stdio.h> // IWYU pragma: export
+	#define fseek _fseeki64
+	#define ftell _ftelli64
+#endif
+
 // Apple has deprecated `sprintf` since Xcode 14 (for macOS 13), but we use it solely in
 // contexts where both the size of the buffer *and* max size of the printed string are
 // known statically, which GCC thus checks for.