This expression means 'anyhow', 'anyway', or 'in any case'. You use it when you want to set aside specific details and focus on the main point or conclusion. For example, if two people have different opinions but the outcome is the same, you can use this to acknowledge both but move on. It often appears in discussions, polite arguments, or when you want to wrap up a topic.

There are three forms: いずれにしても (most common and neutral), いずれにしろ (slightly more colloquial), and いずれにせよ (formal/literary). All mean essentially the same. They can be used at the start of a sentence or after stating a condition, like 'whether A or B'. When used after a clause, it means 'whether (that is true) or not'.

This is an N1-level phrase, so it is more common in written language or formal speech. In casual conversation, you'd more likely hear 'どっちにしても' or 'とにかく'. But if you want to sound a bit intellectual or formal, this works.