If you want to clean install Windows 10 to an SSD, you should, first of all, create a Windows 10 installation media by using Microsoft Media Creation Tool, boot your PC from that media, and finally installing Windows 10 to the SSD. Note that if the SSD is brand new, you can easily get a fresh install. But if it is a used drive that has data saved, clean the hard drive first to make it unallocated space (back up first if necessary), then you can do the installation. In view of this, many users consider it more convenient to transfer Windows 10 on SSD, avoiding the very troublesome backup and installation.
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If your Windows 10 is running just fine but you want to transfer Windows 10 to SSD, migrating Windows 10 is the best/easiest procedure for extracting the old windows 10 OS from the old hard drive. With professional disk partition manager, it should be an easy task. Here we recommend using MiniTool Partition Wizard Free to help you, for it not only allows you to migrate Windows 10 only but also all content on the system disk. This is significant. If your SSD has a small capacity, migrating Windows 10 is the best choice. If your SSD has a large capacity, migrating all content on the system disk is also a nice choice. Download the freeware first.