Meanings ot the expression "That's it" vs "This is it"

Could someone please let me know the different meanings ot the expression"That’s it"?

could anyone please let me know the meaning of this expression"This is it"?
Thanks a lot.

could someone please tell me the meaning of"That’s it" and “This is it” in speaking?

These expressions could be used with several subtle differences in meaning, but they usually have somewhat similar meanings. Perhaps you could find more on etcetera.

Some examples:

  • That’s it! (You got the answer to our problem or question! / I’ve had enough of your bad behaviour, I will take measures now.)

  • That’s it. (We’re finished now, this is the end.)

  • That’s it? (Is this the end?)

  • This is it can mean roughly the same but is a bit stronger (whatever that means; I know, it is vague). Perhaps you could say that you use it when something more important happens; but the difference is not consistent. I’d use them as near-synonyms.

1. “I’m tired of all the chores I’m doing at home, no one’s helping. You’re kids are all sleepy head and I exactly knew where they got that. That’s it. I’m leaving” (negative similar to…)

That’s it. —I’m frustrated and I’m ending this. I’m finished with all this stuff, I’m not going to do this anymore.

2. A: “I suggest we would strengthen our advertising and make clear evaluations on our progress.”
B: “That’s it! I guess this would be the best solution.”

That’s it! —Great idea! This is what I’ve been looking for.

3. “I like playing the piano, blogging, and I also study English on weekdays. That’s it.”

That’s it.—That’s all. That’s all that I can say.

4. “My boss wants to meet you tomorrow morning.”
“This is it. I guess you’d be granted promotion for a great job last week.”

This is it.—This is what we’ve been waiting for. This is our chance.

5. This is it! I got the solution for our Algebra problem.

This is it!— After all my efforts, finally I got it. similar to #2.

haha funny. I just want to make a correction from my previous post above (Nov 24).

I said in #1. "I’m tired of all the chores…You’re kids are all sleepy head
it should be “…Your kids are all sleepyheads…”