a decision that is easy, and that you do not need to think about, used when you want to emphasize that it is really very easy 无需动脑子的事,简单的事
Joining the savings plan is a no-brainer. Just do it.
参加储蓄计划的事根本不用考虑了,赶快行动吧。
Examples from the Corpus
no-brainer• Continuing down this highly successfulroad should be a no-brainer.• It used to be a no-brainer.• It should have been a no-brainer.• Joining the plan is a no-brainer.• The advent of interleague play next season makes it a no-brainer.• If you ask me, it's a no-brainer. Of course you should accept the job.• Until recently, the decision was a no-brainer.• The movie is a completeno-brainer, but enjoyable.