benjamin
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For households with W-2 + Schedule C income

Know where your next dollar should go

Extra principal, Roth conversion, 529, or Solo 401(k)? benjamin models your federal taxes, mortgage, retirement, and college savings together — so you see what each choice costs and saves before you move the money.

Start modeling freeSee how it works

Free to start. No credit card, no bank linking — your numbers stay yours.

Taxes first, not as an afterthought

Every allocation shows its federal tax impact at your marginal rate — conversions, deferrals, and deductions included.

One model, every goal

Enter income, accounts, and debts once. Tax, mortgage, retirement, and college projections stay in sync automatically.

Scenarios in minutes, not weekends

Compare what-ifs across tax liability, net worth, and goal progress — without rebuilding a spreadsheet every season.

Planning workspaces

Four goals competing for the same dollars

Mortgage, retirement, college, and taxes usually live in separate spreadsheets that never talk to each other. benjamin connects them, so a dollar moved in one place shows its effect everywhere else.

Tax planner
Project this year's federal liability from W-2 wages and Schedule C profit. Test Roth conversions, Solo 401(k) deferrals, and withholding changes — and see the marginal rate on each move.
Mortgage payoff
See exactly how much interest and time extra principal buys you — and whether those dollars would do more in a tax-advantaged account instead.
Retirement & financial independence
Track progress toward your financial independence number. Adjust contributions and return assumptions and watch the date move in real time.
529 college savings
Spot funding gaps per child before enrollment sneaks up. Contributions, state deduction limits, and timelines stay tied to the same household balance sheet.
Tax Strategist

Know the tax cost before you commit

The Tax Strategist puts a federal tax number on every option — extra mortgage principal, 529 contributions, Roth conversions, retirement deferrals — so you have the trade-offs in hand before the CPA meeting, not after.

  • W-4 withholding simulator with projected year-end liability
  • Roth conversion scheduler that respects your marginal rate
  • Saved scenarios to compare year-end moves side by side
  • Child Tax Credit modeling for qualifying dependents

Sample trade-off

Putting $800/mo toward mortgage principal saves $47,200 in interest and pays off the loan 3.2 years sooner — but earns no federal tax benefit.

The same $9,600 deferred into a Solo 401(k) cuts this year's federal tax by $2,304 at a 24% marginal rate. benjamin lays out both paths so you choose deliberately, not by default.

Set up in one evening

Create your household, enter the numbers you already know, and run your first scenario the same night.

01

Map your household once

Add W-2 jobs, Schedule C businesses, dependents, property, debt, and accounts. Every workspace — tax, mortgage, retirement, college — reads from the same model.

02

Compare scenarios side by side

Change withholding, schedule a Roth conversion, redirect a surplus. Federal tax, net worth, and goal progress update together before you commit a dollar.

03

Walk into your CPA meeting prepared

Show up with the trade-offs already modeled and the marginal rates attached. benjamin runs the numbers — you make the call.

FAQ

Common questions

Straight answers before you sign up.

Your year-end surplus has somewhere better to be

Stop guessing between the mortgage, the 529, and the Solo 401(k). Map your household tonight and see the trade-offs with the tax math already done.

Start modeling free

Free to start. No credit card required.