TaxCalculator
Plan Roth conversions and quarterly tax.
A this-year tax planner for self-managing retirees.
Features
Live Headroom
One hero number tells you how much more you can convert and stay inside your target bracket. Pick 12%, 22%, 24%, or 32% and the headline updates.
Marginal-Rate Curve
A chart of the tax on your next dollar against additional conversion. Bracket edges show as step-ups; SS-torpedo and OBBBA-phaseout regions show as bumps above the nominal rate.
Cliff Detection
IRMAA tiers (with 2-year forward perspective), LTCG 0%/15% threshold, OBBBA senior-bonus phaseout end — each with distance in dollars and annual cost if crossed.
Target / Paid / Left
A progress bar tracks your quarterly estimated payments against the safe-harbor target (lesser of 90% of this year or 100%/110% of last year). Federal and state, per quarter.
Pay-as-you-Convert
Enter a hypothetical conversion and see the additional federal tax to add to your next 1040-ES voucher. Or use the December-withholding suggestion to cure a whole-year shortfall at once.
Required Withdrawal (RMD)
IRS Uniform Lifetime Table lookup with the SECURE 2.0 age-73 / age-75 split. Flags the double-RMD trap if you deferred your first RMD past April 1.
State Tax, 50 + DC
Full math for 22 no-income-tax and flat-rate states. Progressive states get an info card with the top marginal rate and retirement-income treatment — honest, not approximated.
Printable PDF Report
Three pages modeled on a CPA tax-planning analysis: income summary, federal + state calculation, headroom analysis — with source citations on every constant.
JSON Export & Import
Export your household profile as a plain-JSON file to share with your tax preparer or move to a new device. Schema-versioned envelope, ready for next year's import.
Why TaxCalculator?
Built for the this-year horizon
Long-term planners answer “what’s my retirement plan?” TaxCalculator answers “what do I do this calendar year, and by when?”
Engines, not approximations
Cap-gains stacking, SS-torpedo, OBBBA phaseout, IRMAA cliffs, RMD basis — all modeled, not estimated.
Per-state treatment, honestly
Flat-tax states get the exact computation. Progressive states get the top rate and exemption flags with a “consult your preparer” note — not a misleading approximation.
No assumptions about your tax preparer
Export your profile as JSON and email it to your CPA. Import it back next year. Your data, your workflow.
Completely on-device
No account, no analytics, no network calls. Your tax data never leaves your phone.
All five filing statuses, all 50 states
MFJ, QSS, Single, HoH, MFS. Every state plus DC has at least an info card; 22 have full computation.
No account. No tracking. Your tax data stays on your phone.
100% on-device. No sign-in, no analytics SDK, no telemetry. The only network path is Apple StoreKit if you choose to tip. Your household profile saves to a plain JSON file in the app’s Documents directory.
Not tax advice. TaxCalculator is an estimator. It is not tax advice. Confirm any decision with a CPA, EA, or qualified tax preparer before acting on it. Supports all five filing statuses (MFJ, QSS, Single, HoH, MFS) and the 2026 tax year.