10.6M base salary + 5.3M bonus

Hi,

I just got the following job offer:
- Monthly: 890.000yen
- Bonus: 5.3mill yen (June). This is certain not guaranteed.

I'm married with a toddler and a baby. My office is close to Nihombashi. I would like to live about 30min max in metro from there.

Is this salary good enough?
I'm completely unaware of the cost of living. I've done a lot of google search and my fear is that rents are very high (3.5k - 4k).

Thoughts and recommendations are welcome.

That's pretty good. If you search average household income for Tokyo I think you'll find a figure around 6M. Lots (and lots) of people manage on 3M/year or less.

Yes, that�fs a good salary and you should be able to live comfortably on that (background: I am in that bracket as well).
Regarding the bonus, it obviously depends on you company and your contract, but in my experience in many companies those bonuses are nearly guaranteed. Eg in my company if you work okay, you get the bonus. Only if your work is really bad you get a reduced bonus (somewhere between 40-80%). Obviously the rules in your company might be different. But eg in EU when someone speaks about bonus, it�fs real added bonus that you might get for some really excellent performance or excellent performance of the company.