There is something about passwords. If you're relying on some password manager (and if you aren't already using one, then suggest you search for one :D) then you'd be aware password managers can generate random passwords for you.
But there are times where you might just need a "temporary fix" (or worse don't have a password manager on a server that you SSH through), and you're running out of random ideas to quickly come up with something decently secure. Worse, if you rely on tiling manager on Linux like I do (bspwm, i3, etc...), sometimes it's quicker to fire up a terminal than switching to a web browser.
So, here are some tips.
Essentially, we're creating a random password on-demand using simple command line available on your personal device.
For Windows, fire up PowerShell. Once you're in PowerShell, type:
PS C:\> Add-Type -AssemblyName 'System.Web'
PS C:\> $password = [System.Web.Security.Membership]::GeneratePassword(<length>, <number of non-alphanum characters>)
PS C:\> $password
<output>Load "System.Web" to run PowerShell internal methods provided by System.Web.Security.Membership
<length>: the length of your password
<number of non alphanum characters>: number of non-alphanumerical characters you need in the password
Save either in your profile or you can save this as a ps1 file to load when needed.
For Linux or Mac, I would suggest you set this up as an alias in your .profile / .bashrc / .zshrc:
$ cat ~/.zshrc | grep rng
rng='dd if=/dev/urandom bs=1 count=<length> 2>/dev/null | base64 -w 0 | rev | cut -b 2- | rev'<length>: the length of your password
Hopefully useful for someone who needs a quick and dirty way to create a complex enough password for temporary use.