How do I say ‘what a relief’?
Natural after uncertainty, danger, pressure, or waiting has ended.
终于松了口气
I can finally breathe easy / what a relief.
Finally let out a breath.
I can finally breathe easy / what a relief.
WHEN IT FITS
The physical image of releasing a held breath maps closely to the emotional change.
The physical metaphor is central: 松口气 pictures releasing a held breath, and the relief is understood through that bodily image. Do not drop 气 — 松口 means to soften a negotiating position, a completely different meaning. 还好没事 (“luckily everything is fine”) centers relief on a bad outcome that didn’t happen; 放心了 (“I can set my mind at ease now”) emphasizes the mental letting-go.
HOW PEOPLE ACTUALLY SAY IT
听说检查结果没问题，我终于松了口气。
When I heard the test results were fine, I finally felt relieved.
Reassuring news项目总算做完了，大家都松了口气。
The project is finally done. Everyone breathed a sigh of relief.
Pressure endingCHOOSE BY SITUATION
还好没事
Luckily, everything is okay.
Relief centers on avoiding a bad outcome