としたって / としたところで

1. 1Even X, seen from X's standpoint, is no exception to what follows.Ex. 1
2. 2Even supposing the stated action or situation, the outcome would be unchanged or futile.Ex. 2

Both forms occur in speech and writing; としたって leans colloquial, としたところで leans written and slightly formal. With としたところで the main clause usually shows that the supposed action would change nothing (今さら謝ったとしたところで、もう遅い), though a reassuring conclusion is also possible (雨が降ったとしたところで、屋内開催だから問題ない). With としたって the main clause can be positive or negative (失敗したとしたって、いい経験になる).

• たところでN1「たところで」 attaches only to the verb た form and has no usage for a person's stance; in the sense of 'even if (you) do it, it won't help,' it is largely interchangeable with 「としたところで」 when the latter attaches to a verb, but it lacks the hypothetical nuance of 「とする」. It can also mean 'at most, only to a limited degree,' and is neutral in register.
• にしたってN1In the person's-stance usage, this pattern is interchangeable with 「にしたって」. 「にしたって」 can also acknowledge an established fact and then add criticism, attaches directly to nouns and な-adjectives, and can follow question words to mean 'no matter...'; with 「としたって」, the concession is hypothetical only, and the following clause is usually negative.
• としてもN2「としても」 corresponds only to the hypothetical-concession sense; it is neutral in register and also works in written language. Its following clause is not limited to negative results and can express volition or assertion, so in formal writing it is best to change 「としたって」 to 「としても」.
• にしてもN2「にしても」 is neutral in register: the first item is usually a known fact and the second is an evaluation or complaint, not limited to 'it won't help.' No 「だ」 is added after nouns, and it has the parallel usage 「AにしてもBにしても」; the two are similar when expressing a person's stance.
• といえどもN1Both mean 'even if...'. 「といえども」 is written language with a solemn tone, and its second item is mostly a prohibition, obligation, or assertion; 「としたって」 leans colloquial, carries a resigned 'it's no use anyway' feeling, and its second item is mostly a negative judgment.
• とてN1「とて」 also has two usages — attaching to nouns to mean 'even if it is..., still' and attaching to verbs and adjectives to mean 'even if..., still' — with the following clause likewise mostly negative, so the meanings are close. However, 「とて」 is archaic, used mainly in written texts, novels, or formal speech, and is unsuitable for everyday conversation.

たところで also suggests futility but follows a た-form (or だった) directly, without the explicit supposition of として; にしたって overlaps with the noun use; としても and にしても are broader concessive forms that do not by themselves imply futility; といえども and とて are literary "even" expressions.