While WhatsApp is one of the fastest and easiest ways to communicate with people, it is also quite misused.
Anyone can send a message to anyone on WhatsApp and that might cause unnecessary disturbance to the recipient.
The easiest way to stop such spam and unwanted messages is to block the sender, but what if you want to know whether or not you have been blocked.
While there is no certain way to know that, you could check if the profile picture of the person is visible or not. If it is not, you are likely blocked.
Besides the profile picture, you can check if the status and online status are visible. If they are not, they have blocked you.
Messages you send to the contact only show one checkmark (message sent) and never a second checkmark (message delivered).
Calls you attempt to make to the contact won't go through, and you won't hear a ringing sound. That means you are likely blocked.
If you're an admin of a group chat, you won't be able to add the contact to the group if they've blocked you.