Bitwarden Password Generator
bitwarden.com
Generates a random password or passphrase without leaving the page
useapassphrase.com
Generates a word-based passphrase and shows how long it would take to crack.
One page that hands you a four, five or twelve word passphrase and, next to it, runs Dropbox's zxcvbn estimator so you can see the difference between a memorable phrase and the password you were about to reuse. Generation happens in your browser and the page says so explicitly; it also points at offline diceware for anyone who does not want to trust a web page at all. The teaching is the point — it is a demonstration as much as a generator.
Questions
Works the moment the page loads. No account, no email, no trial. You cannot choose or inspect the word list, and there is no vault — you copy the phrase and store it yourself.
No. Use A Passphrase does the work inside your browser, so the file never leaves your device — you can load the page, disconnect from the network, and it still works. That makes it a reasonable choice for material containing personal data.
You cannot choose or inspect the word list, and there is no vault — you copy the phrase and store it yourself.
Alternatives
Same category or same task, ordered by how closely they overlap.
bitwarden.com
Generates a random password or passphrase without leaving the page
coveryourtracks.eff.org
Measures how uniquely identifiable your browser is to a tracker
dnsleaktest.com
Reveals which DNS servers are actually resolving your queries right now
haveibeenpwned.com
Tells you which data breaches your email address has turned up in
jimpl.com
Shows the hidden EXIF in a photo, including GPS, and gives you a stripped copy
justdeleteme.xyz
A directory of the direct links for deleting your account on hundreds of sites