Here are the main ways to check if someone has blocked you on WhatsApp:

1. Last Seen and Online Status
   • If you can no longer see a contact's "last seen" or "online" status in the chat, this may indicate you are blocked. However, they may have simply changed their privacy settings to hide this from everyone.
2. Profile Picture
   • If the person's profile picture disappears or stops updating from your view, it is a sign of being blocked. Keep in mind some users do not use or frequently update their pictures, so use this with other clues.
3. Message Delivery Checkmarks
   • Messages you send show accompanying tick marks:
     • One gray tick means message sent.
     • Two gray ticks mean message delivered.
     • Two blue ticks mean message read (if read receipts enabled).
   • If your messages to that contact always show only one gray tick and never two, it likely means you are blocked.
4. Status Updates
   • When blocked, you can no longer see the contact's status updates (photos, videos, texts that disappear after 24 hours).
5. WhatsApp Calls
   • Calls to a contact who blocked you will not ring on their side.
6. Trying to Add to Group
   • Attempting to add the contact to a WhatsApp group may result in an error or the contact not appearing even if added.
7. Profile Picture Refresh Trick
   • Tap on the profile picture in chat to enlarge it. If the picture disappears, it strongly suggests you are blocked.

No single sign definitively proves blocking because some can be due to privacy settings or network issues. But combining several of these clues provides a strong indication that you are blocked by someone on WhatsApp. To summarize the strongest combined signs:

• No last seen or online status
• No profile picture or updates
• Messages always show one tick only
• Can't see status updates
• WhatsApp calls don't ring
• Unable to add to groups

These confirm you are very likely blocked on WhatsApp by that contact. Would you like me to explain any of the methods in more detail or help with anything else?