diff --git a/include/mimalloc/types.h b/include/mimalloc/types.h
index 6a0ac955..ab235499 100644
--- a/include/mimalloc/types.h
+++ b/include/mimalloc/types.h
@@ -197,8 +197,8 @@ typedef int32_t  mi_ssize_t;
 #define MI_SMALL_PAGE_SIZE                (MI_ZU(1)<<MI_SMALL_PAGE_SHIFT)
 #define MI_MEDIUM_PAGE_SIZE               (MI_ZU(1)<<MI_MEDIUM_PAGE_SHIFT)
 
-#define MI_SMALL_OBJ_SIZE_MAX             (MI_SMALL_PAGE_SIZE/8)   // 8 KiB on 64-bit
-#define MI_MEDIUM_OBJ_SIZE_MAX            (MI_MEDIUM_PAGE_SIZE/8)  // 64 KiB on 64-bit
+#define MI_SMALL_OBJ_SIZE_MAX             (MI_SMALL_PAGE_SIZE/4)   // 16 KiB on 64-bit
+#define MI_MEDIUM_OBJ_SIZE_MAX            (MI_MEDIUM_PAGE_SIZE/4)  // 128 KiB on 64-bit
 #define MI_MEDIUM_OBJ_WSIZE_MAX           (MI_MEDIUM_OBJ_SIZE_MAX/MI_INTPTR_SIZE)
 #define MI_LARGE_OBJ_SIZE_MAX             (MI_SEGMENT_SIZE/2)      // 16 MiB on 64-bit
 #define MI_LARGE_OBJ_WSIZE_MAX            (MI_LARGE_OBJ_SIZE_MAX/MI_INTPTR_SIZE)