California Income Tax Calculator (FTB rate schedules X, Y, Z, 1%–12.3% + 1% over $1M)

Understanding the California income tax calculator — concept and principle

This calculator estimates California state income tax from your California adjusted gross income, filing status, itemized deductions and exemption credits. It gives taxable income, the deduction used, tax from the rate schedule, the Behavioral Health Services Tax on very high incomes, the effective and marginal rates and the monthly amount. Figures use the 2025 tax-year schedules (returns filed in 2026).

Only the top slice of income is taxed at 9.3%; averaged over all income the rate is about 5%.

How it is calculated

Taxable income = California AGI − the larger of the standard deduction ($5,706 single or married filing separately; $11,412 joint, head of household or surviving spouse) and itemized deductions.
Tax from the Franchise Tax Board rate schedules: nine rates from 1% to 12.3%; Schedule X (single), Y (joint, brackets about twice as wide) and Z (head of household).
Minus exemption credits.
Plus the 1% Behavioral Health Services Tax on taxable income above $1,000,000.
Effective rate = tax ÷ AGI; marginal rate = rate on the next dollar.

The principle

California uses a progressive income tax: each slice of taxable income is taxed at the rate of its own bracket, so moving into a higher bracket only raises the rate on the income inside that bracket. That is why the effective rate is always lower than the marginal rate. Brackets are adjusted for inflation each year. Unlike federal tax, California taxes capital gains as ordinary income and uses exemption credits instead of personal exemptions.

Worked example

Default inputs: single, California AGI $95,000, standard deduction, no exemption credits.

Deduction used = $5,706 (standard, larger than the $0 itemized).
Taxable income = 95,000 − 5,706 = $89,294.
Tax from Schedule X ≈ $4,743, with the top slice taxed at 9.3%.
No Behavioral Health Services Tax (taxable income below $1,000,000).
Effective rate = 4,743 ÷ 95,000 ≈ 4.99%; about $395 a month.

Each point is the calculator re-run with only “California adjusted gross income (USD)” changed; the gold point is the default example. Change the inputs above and this chart follows your numbers.

California adjusted gross income (USD)	California income tax (USD)
23,750	250
47,500	1,043
71,250	2,628
95,000	4,743
118,750	6,952
142,500	9,160
190,000	13,578

How to read the result

The effective rate is the share of income that goes to state tax; the marginal rate is what an extra dollar of income would cost. Exemption credits for yourself and dependents reduce the result further, and other credits may apply. For budgeting, add federal tax, Social Security, Medicare and State Disability Insurance, which are not included here.

Common mistakes

Entering federal AGI when California adjustments differ.
Forgetting to enter exemption credits, which overstates the tax.
Assuming the marginal rate applies to all income.
Using 2025 brackets for 2026 income without checking the FTB's updated schedules.

Keep in mind: This is a simplified estimate based on the published schedules. Check the FTB instructions or a qualified tax professional before filing. This is not tax advice.

Frequently asked questions

What is the top California income tax rate?

12.3% in the schedules, plus 1% on taxable income above $1,000,000.

Why is my effective rate lower than my bracket?

Only the income inside each bracket is taxed at that bracket's rate.

Does California tax capital gains differently?

No. They are taxed as ordinary income at the same rates.

Sources: California Franchise Tax Board, "2025 California Tax Rate Schedules" and "2025 Instructions for Form 540"

Checked 9 Nov 2026. California Franchise Tax Board, “2025 California Tax Rate Schedules” (Schedules X, Y, Z) and “2025 Instructions for Form 540” (standard deduction 5,706 / 11,412 USD, line 62 Behavioral Health Services Tax: 1% of taxable income above 1,000,000 USD).

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