diff --git a/layout.c b/layout.c
index 26b6273..56c4d1b 100644
--- a/layout.c
+++ b/layout.c
@@ -215,7 +215,7 @@
 int layout_sanity_checks(const struct flashprog_flashctx *const flash, const bool write_it)
 {
 	const struct flashprog_layout *const layout = get_layout(flash);
-	const chipsize_t total_size = flash->chip->total_size * 1024;
+	const chipsize_t total_size = flashprog_flash_getsize(flash);
 	const size_t gran = gran_to_bytes(flash->chip->gran);
 	int ret = 0;