How to tell if someone blocked me on WhatsApp without asking them

Don't call or send text messages to that contact expecting a response - that won't tell you anything because if they blocked you, you simply won't see a delivery confirmation anywhere, and you could end up harassing someone without really knowing what happened. What you can do is check a few things that are pretty revealing. Open the chat and see if you can view their profile picture, status, or last seen. If you used to see all that and suddenly you don't see anything, it's likely they blocked you or changed their privacy settings. Try creating a group and adding them to it - if you get an error message like "unable to add this contact," that's a sign of blocking.

Another method that works pretty well is checking whether your messages have two gray checkmarks (delivered) or never reach that status. If you always see one gray checkmark and it never changes to two blue checkmarks after a reasonable amount of time, it could be that they blocked you. The same goes if they used to be online all the time and suddenly you never see that information anymore. Now, to be honest: some of these indicators could also just mean they changed their privacy settings or they simply don't have internet, so nothing is 100% certain without asking. But if several of these signs line up, the probability goes up quite a bit.

That person's profile on WhatsApp is your best indicator: if you can't see their photo, status, or "last seen," they probably blocked you (though they could've also disabled those privacy settings, so it's not 100% certain). The most reliable way is to try adding them to a group again - if WhatsApp won't let you do it, that's pretty clear confirmation they blocked you 🚫

Avoid trying to confirm the block through groups where that person is, because if they blocked you, you still won't be able to see them writing or their statuses, so you'll end up just as clueless. The most straightforward thing is to check if their profile picture and status suddenly stopped appearing in your chat with that person, though it's not 100% reliable either because they could have also disabled those privacy settings.