As we all knows Windows 7 comes with many new and redesigned things and on of them is calculator which has new GUI and new options.
"grdcityboy" has created a small application which looks very similar to Windows 7 Calculator: However, XP version Windows 7 calculator can work on standard mode only and Microsoft .Net Framework 3.5 is required to install. You can simply use it by just opening CALC.EXE file from the downloaded folder Or You can use it as a default calculator in xp for this you will need to replace the original one with this for this you will need REPLACER which you will find in RECOMMENDED section. Just drag the original file which can be find in %windir%system32 in replacer and then drag downloaded file in it, that’s it now you can use windows 7 calculator as default one in xp