diff --git a/libfwupdplugin/fu-device.c b/libfwupdplugin/fu-device.c
index af5389903..1586c9edb 100644
--- a/libfwupdplugin/fu-device.c
+++ b/libfwupdplugin/fu-device.c
@@ -3707,8 +3707,8 @@ fu_device_prepare_firmware(FuDevice *self, GBytes *fw, FwupdInstallFlags flags,
 			g_set_error(error,
 				    FWUPD_ERROR,
 				    FWUPD_ERROR_INVALID_FILE,
-				    "firmware is %04x bytes larger than the allowed "
-				    "maximum size of %04x bytes",
+				    "firmware is 0x%04x bytes larger than the allowed "
+				    "maximum size of 0x%04x bytes",
 				    (guint)(fw_sz - priv->size_max),
 				    (guint)priv->size_max);
 			return NULL;