--- title: "Log In to an Instance of SQL Server (Command Prompt) | Microsoft Docs" description: 'Learn about the "sqlcmd" utility. See how to use it in a command prompt to test connectivity to an instance of SQL Server.' ms.custom: "" ms.date: "03/14/2017" ms.prod: sql ms.prod_service: high-availability ms.reviewer: "" ms.technology: configuration ms.topic: conceptual helpviewer_keywords: - "logins [SQL Server], named instance of SQL Server" - "log ins [SQL Server]" - "logins [SQL Server], default instance of SQL Server" - "command prompt [SQL Server], logins" - "logging in [SQL Server]" ms.assetid: f67c11e3-c519-40c9-82c1-07efa9d9985e author: markingmyname ms.author: maghan --- # Log In to an Instance of SQL Server (Command Prompt) [!INCLUDE [SQL Server](../../includes/applies-to-version/sqlserver.md)] This topic describes how to test connectivity to an instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)], use the **sqlcmd** utility. ## #### To log in to the default instance of SQL Server 1. From a command prompt, enter the following command to connect by using Windows Authentication: ``` sqlcmd [ /E ] [ /S servername ] ``` #### To log in to a named instance of SQL Server 1. From a command prompt, enter the following command to connect by using Windows Authentication: ``` sqlcmd [ /E ] /S servername\instancename ``` ## See Also [sqlcmd Utility](../../tools/sqlcmd-utility.md) [osql Utility](../../tools/osql-utility.md)