Quarterly Estimated Tax Calculator
Plan 2026 federal estimated payments using annual tax, withholding, and prior-year safe harbors. See installments, due dates, and a projected…
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Self-Employment Tax Calculator
Estimate 2026 regular self-employment tax from net profit and your own W-2 wages. See Social Security, Medicare, and the deductible…
SEP IRA Contribution Calculator
Estimate 2026 SEP IRA contribution capacity from business profit or eligible wages. Apply the correct reduced rate, compensation limit, and…
Solo 401(k) Contribution Calculator
Estimate 2026 solo 401(k) employee, employer, and catch-up contributions. Include other-plan deferrals and the special self-employed income limits.
Roth Conversion Calculator
Compare a Roth conversion with keeping traditional funds. Include conversion tax, future tax, growth, and the opportunity cost of outside…
Window Replacement Cost Calculator
Calculate a window replacement budget from your quoted unit prices. Group different windows and include labor, removal, finishing, tax and…
Roof Replacement Cost Calculator
Estimate a roof replacement budget from measured area and your quoted prices. Separate materials, waste, labor, tear-off, tax and contingency.
HVAC Replacement Cost Calculator
Build an HVAC replacement budget using your equipment and installation quote. Include extra work, permits, tax, contingency and verified incentives.
Heat Pump Savings Calculator
Compare heat-pump heating costs with gas or electric resistance. Include seasonal COP, backup heat, energy prices and the extra cost…
Solar Battery Payback Calculator
Estimate battery payback after charging losses, lost export credits, maintenance and replacements. Compare cash savings with your separate backup-power priorities.