How much self-employment tax will I owe in California?

15.3% federal SE tax applies to 92.35% of net income; federal and California income taxes may also apply.

Do I have to pay quarterly estimated taxes?

Yes. If federal tax due is $1,000 or more, pay April 15, June 15, September 15, and January 15.

Yes. Half of SE tax is deductible from AGI; this calculator applies it automatically.

No. It is a planning estimate; credits, deductions, and multi-state work can change your filing result.

California taxes freelance income at 1% to 12.3%, plus a 1% mental-health surcharge above $1M. No separate state SE tax applies.

Yes. California generally requires estimated payments when expected state tax is $500 or more; Form 540-ES uses a 30/40/0/30 schedule.