quantcalc

Retirement projection + IRS contribution-limit status. Tax-free headroom you're leaving open, or 6% excise tax if you're over. Free.

Monte Carlo portfolio stress test: 100 scenarios (1,000 in PRO), percentile outcomes, drawdowns, survival odds. Free, private.

Calculate Required Minimum Distributions from IRA and 401k. 2026 IRS Uniform Lifetime Table. Multi-year projections. Free.

Avoid the IRS Form 2210 underpayment penalty (8% rate). Quarterly safe-harbor payment for Uber, DoorDash, 1099 income. Free.

1040-ES safe-harbor + Solo 401(k)/SEP-IRA sizing + §199A QBI phase-out. Avoid Form 2210 penalty, hit April 15 plan deadline. Free.

Years-to-FIRE with real-return inflation + ACA 400% FPL cliff overlay for pre-Medicare bridge years. $10K/yr subsidy cliff. Free.

Take-home pay + W-4 status check. Per-paycheck adjustment for refund or balance-due surprises. 2026 brackets, FICA, state. Free.

Plan retirement with a 100-path Monte Carlo using 5-asset correlated returns. Free, runs locally, no signup.

Pro-Rata Rule (Form 8606) check + IRMAA 2-yr-lookback Medicare surcharge + Roth vs Traditional decision. Three traps. Free.

Two cliffs to watch: 0% LTCG bracket headroom + 3.8% NIIT cliff at $200K/$250K MAGI. Sell now, split across years, or wait. Free.