Many free FTP clients are available for Windows. Here I have listed some popular free FTP clients, please check it out.
FileZilla is free and cross-platform FTP software, consisting of FileZilla Client and FileZilla Server. Binaries are available for Windows, Linux, and Mac OS X. It supports FTP, SFTP, and FTPS (FTP over SSL/TLS).
It got many features like IPv6 support, drag & drop support, remote file editing etc. It is an open source project, free to use, as it supports resume of uploads it is used by many users across the world.
FireFTP is a free, open source, cross-platform FTP client for Mozilla Firefox in the form of an add-on. Fire FTP is available in over 20 languages and got SSL/TLS/SFTP support. Directories and sub-directories can be compared side-by-side. FireFTP is charityware and runs on platforms that Firefox supports.
Cyberduck easy to use interface allows you to connect to FTP, SFTP, WebDAV, Amazon S3, Windows Azure, Rackspace Cloud etc. Files on the server can be easily edited using any external editor application. It is currently available for Windows, Mac and is free to use.
Core FTP is a secure FTP client for Windows, developed by CoreFTP.com. Features include FTP, SSL/TLS, SFTP via SSH, and HTTP/HTTPS support. Secure FTP clients encrypt account information and data transferred across the internet, protecting data from being seen or sniffed across networks. Core FTP is a traditional FTP client with local files displayed on the left, remote files on the right.
WinSCP (Windows Secure CoPy) is a free and open source SFTP, SCP, and FTP client for Microsoft Windows. Its main function is secure file transfer between a local and a remote computer. Beyond this, WinSCP offers basic file manager and file synchronization functionality. For secure transfers, it uses Secure Shell (SSH) and supports the SCP protocol in addition to SFTP.