Summary
If you make $39,983 a year living in the region of California, USA, you will be taxed $7,503. That means that your net pay will be $32,480 per year, or $2,707 per month. Your average tax rate is 18.8% and your marginal tax rate is 27.0%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of $100 in your salary will be taxed $27, hence, your net pay will only increase by $73.
Bonus Example
A $1,000 bonus will generate an extra $730 of net incomes. A $5,000 bonus will generate an extra $3,650 of net incomes.