NO. it’s not possible to perform in-place or direct upgrade from Windows 7/8.1 32-bit to Windows 10 64-bit. In simple words, if you want to upgrade to 64-bit architecture of Windows 10 by upgrading the current 32-bit Windows 7/8.1 installation by keeping installed programs and your data, it’s not possible at all.
However, if you don’t mind performing a clean install of Windows 10 after completing the upgrade, you could upgrade to Windows 10 64-bit. But before that, make sure that your PC’s processor supports 64-bit operating system with the help of a free tool called 64bit Checker.
According to Microsoft, users will be able perform clean install of Windows 10 after the upgrade. If you really want to upgrade from 32-bit Windows 7/8.1 to 64-bit Windows 10 without shelling out a single penny, recommend you upgrade your existing Windows 7/8.1 32-bit installation to Windows 10 32-bit first.
Once upgrading your Windows 7/8.1 installation to Windows 10 and activating the copy, download the 64-bit Windows 10 ISO from Microsoft using the Windows 10 Media Creation Tool, create a bootable USB out of it and then install the 64-bit Windows 10. You don’t need to input a serial key during the installation, as your Windows 10 copy will automatically activated after completing the installation. Please go through our activating Windows 10 after a clean install article to know how it works and why you don’t need a product key to activate your Windows 10 installation.
The only catch is that, you’ll need to install device drivers and programs all over again after the clean install.
Lastly, if you are ready to buy the Windows 10 upgrade copy, you can perform a clean install of Windows 10 64-bit by wiping your current Windows 7/8.1 (x86) installation.
One can’t perform an in-place or direct upgrade from 32-bit Windows 7/Windows 8.1 to 64-bit Windows 10. However, you can go for one of the two above mentioned workarounds to legally upgrade to Windows 10 64-bit.
1Per this article, there seems to be no upgrade path to go from 32 to 64. Only clean install. (Which isn't all bad, simply get your Windows 8.1 serial key, do a clean install, then call Microsoft and give them your 8.1 key and they will generate you a new Windows 10 key). – Insane – 2015-09-26T00:03:18.563
@Moab I searched before posting this. look at the structure of the title of that post and if you think this is repeated you could have edited it before. and one more thing that user hasn't asked whether it'll work with the boot able 64bit disk – Wind Chath – 2015-09-26T03:21:16.263
Upgrade to 32bit first, make sure it activates, then do a clean install of 64bit, you cannot upgrade directly to 64bit. – Moab – 2015-09-26T18:53:52.243