Checking in and checking on

Example 1
A: Is there something wrong?
B: No. Just checking in.

Example 2
Jor. Just came by to check on you. Jordan. Come on, Jordan, I know you’re in there. Just came by to see what’s up, see if you’re good.

I don’t really understand what’s the difference between checking in and checking on.
Are they the same, different or similar?

Thank you!!!

To check on someone is to make sure they’re ok. It can also be used for making sure someone is on task. For example you would check on your kid to make sure they’re doing their homework instead of playing video games. You could go check on the status of something, to make sure it’s working right. You might also check on your data if you’re running an experiment or a computer program. It’s a pretty versatile phrase.

Checking in is less versatile. A person checking in with another person usually indicates more of a submissive role. You might check in with your boss before doing something. You might check in with someone periodically to let them know you still exist/are still on task. You might check in with your husband/wife/girlfriend/etc. in a similar manner.

Then you could also say you’re checking in on something or someone, which is basically the same as checking on.