Best IDM Alternative is Xtreme Download Manager XDM. Best Internet Download Manager Alternative is free and Open source Xtreme Download Manager.
XDM (Xtreme Download Manager) is the best free IDM (Internet Download Manager) replacement. It has almost all the features that IDM as, with additional features and it is free and open source (Hosted on GitHub).
Download XDM
Xtreme Download Manager is a powerful tool to increase download speed up-to 500%, save streaming videos from YouTube, DailyMotion, Facebook, Vimeo, Google Video and 1000+ other websites, resume broken/dead downloads, schedule and convert downloads. XDM seamlessly integrates with Google Chrome, Mozilla Firefox Quantum, Opera, Vivaldi and other Chromium and Firefox based browsers, to take over downloads and saving streaming videos from web. XDM has a built in video converter which lets you convert your downloaded videos to different formats so that you can watch then on your mobile or TV (100+ devices are supported)
Features of XDM (Xtreme Download Manager)
Download files at maximum possible speed. ( 5-6 times faster )
XDM can save video from YouTube, Dailymotion, Vimeo, Facebook and thousands of popular video sharing sites.
Works with all modern browsers on Windows, Linux and Mac OS X. XDM supports Google Chrome, Chromium, Firefox Quantum, Vivaldi, and many other popular browsers.
XDM has built in video converter, which lets you convert downloaded video to MP3 and MP4 formats
Supports HTTP, HTTPS, FTP as well as video streaming protocols like MPEG-DASH, Apple HLS, and Adobe HDS. XDM also supports Authentication,Proxy Servers, Cookies, Redirection etc.
Video download,clipboard monitoring, automatic antivirus checking,scheduler, system shutdown on download completion Resumes broken/dead downloads caused by connection problem,power failure or session expiration
Works with Windows ISA, auto proxy scripts, proxy servers, NTLM, Kerberos authentication.