1An adverb meaning 'anyway' or 'in any case', often expressing resignation or a dismissive sense that the outcome won't change no matter what.
どうせ雨が降るから、傘を持っていこう。
It's going to rain anyway, so let's bring an umbrella.
どうせ怒られるなら、正直に話したほうがいい。
If I'm going to get scolded anyway, I'd rather be honest.
彼はどうせ来ないと思って、席を用意しなかった。
I figured he wouldn't come anyway, so I didn't prepare a seat for him.
どうせなら、みんなで一緒に行こうよ。
Since we're doing it anyway, let's all go together.
2An adverb meaning 'at best' or 'at most', used to express a modest upper limit or low expectation.
急いでも、どうせ5分くらいしか変わらないよ。
Even if we hurry, it'll only save about five minutes at best.
この程度の傷なら、どうせ数日で治るだろう。
A scrape this minor will heal in a few days at most.
彼の給料は、どうせ手取り20万くらいだろう。
His take-home pay is probably around 200,000 yen at best.