Can I block someone on WhatsApp without them knowing

Yes, you can block someone on WhatsApp without them knowing. When you block someone on WhatsApp, they will no longer be able to send you messages, see your profile information, or call you on WhatsApp.

The person you have blocked will not receive any notification that they have been blocked. However, they may notice that they are no longer able to see your online status or last seen timestamp, and their messages to you will only show a single check mark, indicating that the message has been sent but not delivered.

It's important to note that blocking someone on WhatsApp is a permanent action, and it cannot be undone. If you decide to unblock someone in the future, you will need to add them back to your WhatsApp contacts and start a new conversation with them.