form hidden input

I have a <form> with a hidden input.. how do I make it so users cant go into the source code and change it? Thanks!
Or another workaround instead of a hidden input?

I have a <form> with a hidden input.. how do I make it so users cant go into the source code and change it?

You can’t. That’s the nature of HTML and the internet.

Or another workaround instead of a hidden input?

It depends on what you are trying to do. Please elaborate.

You can’t. That’s the nature of HTML and the internet.



It depends on what you are trying to do. Please elaborate.

Well its a promo code thing. The person enters the code into the form and it posts into dopromo.php. Although they are able to change the username if they inspect element