diff --git a/host/hackrf-tools/src/hackrf_cpldjtag.c b/host/hackrf-tools/src/hackrf_cpldjtag.c
index 5e0bfcb0..fe3bce23 100644
--- a/host/hackrf-tools/src/hackrf_cpldjtag.c
+++ b/host/hackrf-tools/src/hackrf_cpldjtag.c
@@ -31,7 +31,11 @@
 #include <stdint.h>
 
 #ifdef _MSC_VER
-typedef int ssize_t;
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
 #endif
 /* input file shouldn't be any longer than this */
 #define MAX_XSVF_LENGTH 0x10000
diff --git a/host/hackrf-tools/src/hackrf_spiflash.c b/host/hackrf-tools/src/hackrf_spiflash.c
index f97f2875..ba2c224e 100644
--- a/host/hackrf-tools/src/hackrf_spiflash.c
+++ b/host/hackrf-tools/src/hackrf_spiflash.c
@@ -36,7 +36,11 @@ typedef int bool;
 #endif
 
 #ifdef _MSC_VER
-typedef int ssize_t;
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
 #endif
 
 /* 8 Mbit flash */
diff --git a/host/hackrf-tools/src/hackrf_transfer.c b/host/hackrf-tools/src/hackrf_transfer.c
index 66e8fbc5..0f2923a3 100644
--- a/host/hackrf-tools/src/hackrf_transfer.c
+++ b/host/hackrf-tools/src/hackrf_transfer.c
@@ -43,7 +43,13 @@ typedef int bool;
 #include <windows.h>
 
 #ifdef _MSC_VER
-typedef int ssize_t;
+
+#ifdef _WIN64
+typedef int64_t ssize_t;
+#else
+typedef int32_t ssize_t;
+#endif
+
 #define strtoull _strtoui64
 #define snprintf _snprintf