A lot of times a company will have a decent idea of what their exit is, based on how much money is in their market, or how much similar companies have sold for. When that's the case, you need to ask.
1/3% (and that's generous) of a potentially $1B dollar company might seem like a lot, but after 10 years of dilution how much will you really have left? If your options dilute by 1/4 (also generous), you've made about an extra $80k a year, and that's not even with taxes subtracted. And don't forget the likely higher salary, raises, bonuses, stock grants, and medical care you get at a big 4 company.
It's possible that you can be be assured to make no extra money working for a startup, even with all the extra risk, depending on how those factors play out.
1/3% (and that's generous) of a potentially $1B dollar company might seem like a lot, but after 10 years of dilution how much will you really have left? If your options dilute by 1/4 (also generous), you've made about an extra $80k a year, and that's not even with taxes subtracted. And don't forget the likely higher salary, raises, bonuses, stock grants, and medical care you get at a big 4 company.
It's possible that you can be be assured to make no extra money working for a startup, even with all the extra risk, depending on how those factors play out.