In case you forgot the password, you always have an opportunity to reset it using your account e-mail:
Use the "Sign In" button in the upper right corner, and click on the "Forgot Password" button:
Enter the email you used to register your account and you will receive an email with further instructions.
How to reset the password if you are already logged in? Please go to "Settings and Security", in the Password section click "Change password":
You will receive an email to your Cryptology account email with further instructions.