Is there a W3C valid way to disable autocomplete in a HTML form? When using the xhtml1-transitional.dtd doctype, collecting a credit card number with the following HTML <input type="text" id="cardNumber" name="cardNumber" autocomplete='off'/> will flag a warning on the W3C validator:       there is no attribute "autocomplete". Is there a W3C / standards way to disable browser auto-complete on sensitive fields in a form? Answer: Here is a good article from the MDC which explains the problems (and solutions) to form autocompletion. Microsoft

How do you disable browser Autocomplete on web form field / input tag? How do you disable autocomplete in the major browsers for a specific input (or form field)? Answer: Firefox 30 ignores autocomplete="off" for passwords, opting to prompt the user instead whether the password should be stored on the client. Note the following commentary from May 5, 2014:    The password manager always prompts if it wants to save a password. Passwords are not saved without permission from the user.    We are the third browser to implement this change, after IE and