For file encryption to be secure, it is crucial that you choose strong passwords. This is why Kryptor has a minimum password length of 8 characters, but I recommended using a password of at least 20 characters.
To help the user choose strong passwords, Kryptor displays the entropy of typed passwords. Password entropy provides a measure of how difficult a password is to crack.
Here is a breakdown of entropy and password strength:
When you type in a password, make sure that the entropy is coloured green. A good password is 128 bits or more in entropy.
Do NOT use weak or moderate passwords. These passwords can be cracked more easily and are therefore not suitable for securing data.
You can go to Tools => Password Generator in Kryptor to randomly generate very strong passwords and passphrases. Kryptor allows you to customise the length and types of characters in the password/passphrase.
If you'd prefer to come up with your own passwords, then here are some rules to folow:
If you want to sync your passwords across devices (e.g. with your phone, another computer, etc), then I strongly recommend using Bitwarden.
If you want to store your passwords on your device (offline), then you should use KeePassXC. KeePassXC is especially good for advanced users as it provides lots of customisation.
Both of these password managers are free, open source, and highly regarded within the information security community. There's no reason to pay for a password manager unless you want to support the developers.