true stripes

for real and for true

Genuinely; truly.

ring true

To seem to be correct, or plausible

show one's true colors

To reveal how one really is, as opposed to how one has been portrayed or after having been deceptively and deliberately misleading.

show one's true stripes

To reveal one's real beliefs, sentiments, or character, especially through one's behavior.

so true, bestie

An assertion that something is true or relatable.

too good to be true

Appearing to be exceptionally good, and therefore arousing suspicion of illegitimacy.

true to form

According to one's nature; as expected.