Attached after a verb: 'there is no need to (do something)'; expresses that an action is unnecessary.
そんなに取り乱すには及ばない。冷静に対処しよう。
There's no need to get so upset. Let's deal with it calmly.
来てくれなくても構わないから、無理をするには及ばないよ。
You don't have to come; there's no need to push yourself.
細部まで完璧に仕上げるには及ばない。まずは全体を確認しよう。
There's no need to perfect every detail. First, check the whole.
Attached after a noun: 'cannot compare to; is far inferior to' — used to state that something is not on the same level as something else.
彼のピアノの腕前には及ばないから、コンテストで優勝は難しいだろう。
I can't match his piano skill, so winning the contest would be difficult.
あの店の味には及ばないが、ここも負けてはいない。
It doesn't compare to that restaurant's taste, but this place is not bad either.
彼女の速さには及ばないが、最後まであきらめずに走った。
I couldn't match her speed, but I ran without giving up until the end.