PDF to DOC and other stuff: https://smallpdf.com/
PDF Tools, e.g. unlock, repair etc.: https://www.ilovepdf.com/
DWG to PDF: https://www.zamzar.com/ru/convert/dwg-to-pdf/
Download videos from the Internet:
https://www.y2mate.com – download from youtube in HD with sound
https://y2mate.is/en8/ – download from youtube in HD with sound
https://en.savefrom.net/
https://fastfrom.com
https://yt1s.com/
Download music from Mixcloud: https://www.mixcloud-downloader.com
Download music from Soundcloud: https://scdownloader.net/
Cut a piece from Yourube videoе: https://www.clipconverter.cc/
set link, choose mp4, uncheck start video и end video, set time and voila :-)
Converter of images of different formats: https://www.go2convert.com
PSD, EPS and tons of others.
Font converter, TTF or OTF to web fints:
https://www.font2web.com/
https://everythingfonts.com/woff-to-woff2
FB2 to EPUB:
https://fb2epub.com/en/
https://online-converting.ru/ebook/fb2-to-epub/
IP to HEX
https://www.vultr.com/resources/ipv4-converter/?ip_address=127.0.0.1
Amps to watts:
https://www.center-pss.ru/klk/k416.htm
Cable cross-section calculator based on power or current:
https://kabel-s.ru/info/calc-kabel-sechenie/
Scribd Downloader:
https://scribd.vpdfs.com/