This has always worked for me.

http://keepvid.com/

I agree, keepvid is really simple to save videos from various sites in HD quality. Only java is needed!

If you want to get videos off certain sites I recommend these:

http://en.savefrom.net/

Save from. net is good

Keepvid is another good video downloading tool.

keepvid.com

u forgot the "4k video downloader" for downloading utube clips in the highest possible resolution

i personally use "Download helper" and "4k video downloader"

DownloadHelper works well for most YT videos, but not full HD ones.

For those, I use jDownloader or youtube downloader hd - both free.

usar  freemake video downloader a mi me funciona

http://convert2mp3.net/en/

Works as a copy & paste option, but will also work as an add-on...

I use ATube catcher.

http://www.atube.me

You can download from youtube in multiple formats, the streamcatcher works on some sites, and what I use for screen recording.

For downloads from YouTube:

http://www.flvto.biz/

i use the Chrome extension "video downloader plus" for most pages, for YT flvto.biz

I have an older Mac (OS 10.6. and use
videoblend: http://www.videoblend.org
simple, free, works just fine for youtube - haven't tried it on other sites.

I usually use these sites :
Youtube converter
Mp3 converter
Dailymotion downloader
Facebook video downloader
Soundcloud downloader
Vimeo downloader

Also try this site : Mp3 Juice

Jdownloader2 is pretty good and it can do all files on a page, including images for stuff like insta

Also check this site :  https://youtubetomp3.site/

For twit*** videos I recommend this twit*** video downloader