正常的DWG文件可以通过记事本或者其他文本软件打开，看开头的几个字节就知道版本号了。
记事本中开头的几个字节 | 对应版本号 | 对应AutoCAD能够打开的版本 |
MCO.0 | DWG R1.0 | AutoCAD Release 1.0 |
AC1.2 | DWG R1.2 | AutoCAD Release 1.2 |
AC1.40 | DWG R1.40 | AutoCAD Release 1.40 |
AC1.50 | DWG R2.05 | AutoCAD Release 2.05 |
AC2.10 | DWG R2.10 | AutoCAD Release 2.10 |
AC2.21 | DWG R2.21 | AutoCAD Release 2.21 |
AC1001，AC2.22 | DWG R2.22 | AutoCAD Release 2.22 |
AC1002 | DWG R2.50 | AutoCAD Release 2.50 |
AC1003 | DWG R2.60 | AutoCAD Release 2.60 |
AC1004 | DWG R9 | AutoCAD Release 9 |
AC1006 | DWG R10 | AutoCAD Release 10 |
AC1009 | DWG R11/12 | AutoCAD R11/12(LT R1/R2) |
AC1012 | DWG R13 | AutoCAD R13(LT95) |
AC1014 | DWG R14 | AutoCAD R14、14.01(LT97/LT98) |
AC1015 | DWG 2000 | AutoCAD 2000/2000i/2002 |
AC1018 | DWG 2004 | AutoCAD 2004/2005/2006 |
AC1021 | DWG 2007 | AutoCAD 2007/2008/2009 |
AC1024 | DWG 2010 | AutoCAD 2010/2011/2012 |
AC1027 | DWG 2013 | AutoCAD 2013/2014/2015/2016/2017 |
AC1032 | DWG 2018 | AutoCAD 2018/2019/2020/2021/2022/2023 |