It's me.
It's I. Both I have seen. which one is correct.
'It is I' can sound rather stuffy to some people.
If you search using the terms nominitive pronoun linking verb, you'll get some hits.
Here's one: Cases of Nouns and Pronouns
Choosing Cases after Linking Verbs
In formal or academic text, we need the nominative or subject form of the pronoun after a linking verb: "It was he who represented the United Nations during the 1960s," "That must be she on the dock over there."
In casual speech and writing, however, that sounds awfully stuffy. Imagine the detective who's been looking for the victim's body for days. He jimmies open the trunk of an abandoned car and exclaims, "It's she!" No self-respecting detective since Sherlock Holmes would say such a thing.
(That same article has a good discussion about case following than and as, as well.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
It is interesting to note that, for most contemporary speakers, the acceptability of It is I as opposed to It's me increases greatly where the former is followed by a relative clause. Thus, while simply e.g. to announce one's presence at the door, "It is I!" would, even to highly educated speakers nowadays, sound almost comically pompous, a sentence such as
It is I who am to blame.
, uttered at least in a suitably formal/dignified context, would be quite unexceptionable.
I entirely agree.
I see your current location is Japan. Are things okay for you?
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
Yes, thanks, Barb D, we're among the very lucky ones unaffected (so far, at least!) by the current tragedy...