Look for places with diverse workforces. My experience is that managers who expect long hours also expect everyone to be 100% aligned with the company vision, and people with different backgrounds tend not to last.

Consider the compensation package a company offers. Companies that want young go-getters are more likely to offer high cash and equity; great benefits packages are better for drawing in risk-averse family types.

Also don't be afraid to ask straight-up what the working hours are like during an interview, ideally from the lowest-ranked person they'll let you talk to.

Disclaimer: I don't have strong data supporting any of this, just my personal experience and intuition from working in the bay area.