FinPlan - High confidence financial planning¶

FinPlan is a financial planning tool that looks forward, not backward. Instead of tracking what you already spent, it answers the question: "If do this, where will I end up?"

It works with AI agents like Claude and ChatGPT to give you precise, valid, grounded answers about your financial future - not guesses.

Why FinPlan?¶

The Problem With Asking AI About Money¶

When you ask an AI assistant about your finances, it's making things up. It doesn't have direct access to real tax brackets, real IRS contribution limits, or a real projection engine. It approximates. It rounds. It hallucinates.

Agents without FinPlan write codes on the fly, don't check it, and then throw it away. It's wasteful!

FinPlan fixes this. It gives the AI agent a set of real financial calculation tools - actual IRS tax tables, actual contribution limits, actual Monte Carlo simulations - so the answers you get back are grounded in fast, well structured math, not guesses.

Think of it as a financial calculator that your AI assistant can use on your behalf. The AI handles the conversation. FinPlan handles the numbers.

Your Data Stays With You¶

Your financial information is sensitive. FinPlan keeps it that way:

Everything stays on your machine - Your data is saved as simple files locally, not uploaded to some service
Take your data anywhere - Your financial plan is a portable file you own
Pick up where you left off - Save your plan, come back next month, load it, and keep going

Math You Can Trust¶

Financial planning tools should get the math right. FinPlan does:

Every penny is exact - No rounding errors, no "close enough." $1,234.56 is always $1,234.56
Real tax brackets, not estimates - The same IRS tables your accountant uses (2024, 2025, 2026)
Thousands of simulations - Instead of one guess about investment returns, FinPlan runs 1,000+ scenarios to show you the range of outcomes
Month-by-month detail - Projections run month by month for up to 72 years, so you can see exactly how things unfold

Current US Tax Code Built In¶

FinPlan doesn't guess at your taxes. It uses the actual published IRS rules:

Federal income tax brackets for 2024, 2025, and 2026
Capital gains rates - Both long-term (0%, 15%, 20%) and short-term rates
Dividend tax treatment - Qualified and non-qualified dividends taxed correctly
Deductions - Standard and itemized deduction logic
401(k) limits - Including catch-up contributions if you're 50 or older
Employer match rules - Vesting schedules and safe harbor requirements
Every account type taxed correctly - Traditional accounts, Roth accounts, HSAs, and taxable accounts all handled according to their real tax treatment

What Can FinPlan Do Today?¶

Consider and Project All Your Accounts (18 Types)¶

FinPlan knows about the accounts real people actually have:

Retirement - Traditional & Roth 401(k) - Traditional & Roth IRA - SEP IRA and SIMPLE IRA - 401(k) Rollovers

Health & Education - HSA (Health Savings Account) - FSA (Flexible Spending Account) - 529 Education Savings Plans

Everyday Accounts - Brokerage accounts - Savings & checking accounts - Money market accounts - CDs (Certificates of Deposit) - Cryptocurrency exchanges

Property & Debt - Real estate (primary home, investment property, vacation home, rental property) with appreciation modeling - Mortgages with full amortization schedules - See your net equity - FinPlan links your mortgage to your property so you always know what you actually own, not just what the house is worth

Customize Your Investment Mix¶

Each account can have its own investment allocation across stocks, bonds, cash, crypto, and other assets. FinPlan enforces what's actually allowed - you can't put stocks in a savings account, for example - and lets you set custom expected returns and volatility for each allocation so projections reflect your real investment choices.

Project Your Financial Future¶

This is the core of FinPlan. Ask questions like "What will my finances look like in 20 years?" and get honest answers:

Range of outcomes, not a single number - See best case, worst case, and everything in between (10th, 25th, 50th, 75th, 90th percentile)
Accounts grow individually - Each account is projected separately based on its own allocation and returns
Take-home values- Taxes and inflation are done correctly, withdrawals from pre-tax accounts are reduced by tax rates or penalties for early withdrawal
Add your contributions - See how regular monthly savings change the picture, and you can set specific timelines including breaks
Compare strategies - Side-by-side comparison of conservative, moderate, and aggressive approaches
"What if" exploration - Change assumptions and see how outcomes shift

Calculate Your Tax Estimates¶

Ask FinPlan what your tax situation looks like and get precise answers:

Federal income tax for any filing status
Your marginal and effective tax rates
Capital gains tax rates based on your income
How much room you have left in your 401(k) this year
How much your employer match is actually worth

Plan for Your Goals (16 Types)¶

Tell FinPlan what you're working toward:

Retirement, emergency fund, home down payment, education, car, debt payoff
Vacation, wedding, business startup, medical expenses, home improvement
Charitable giving, annual taxes, or anything custom

Then FinPlan helps you figure out how to get there:

"How much do I need to save each month?" - Calculate the exact monthly contribution to hit your target
Priority ordering - Fund the most important goals first, then work down the list
Goal dependencies - Don't start saving for a car until the emergency fund is full
Flexible deadlines - Some goals are firm dates, others have wiggle room
Track your progress - See where each goal stands and how likely you are to hit it

Understand Your 401(k) Match¶

Your employer match is free money, but the rules are confusing. FinPlan handles:

All the common match formulas - Safe Harbor, tiered matching, non-elective contributions, and more
Vesting schedules - Know how much of your match you actually get to keep if you leave
"Am I maxing out my match?" - See exactly how much your employer will contribute based on what you put in
IRS limits - Know when you're hitting contribution caps

Know Your Mortgage Inside and Out¶

What's your monthly payment?
How much goes to principal vs interest this month?
See the full payoff schedule from now until the last payment
Track remaining balance over time

FinPlan includes a full Social Security benefits engine built from actual SSA rules — not rough estimates:

Estimate your benefit from your salary - Enter your current salary and years of work to get a Primary Insurance Amount (PIA) estimate
See benefits at every claiming age - Compare your monthly and annual benefit at each age from 62 to 70, with exact early-reduction and delayed-credit calculations
Full Retirement Age lookup - Knows the correct FRA for every birth year, including the fractional-year transitions
Breakeven analysis - "If I claim at 62 vs. 67, when do total lifetime payouts cross?" — answered with one call
Lifetime benefits projection - Project total benefits received over your lifetime, including annual COLA adjustments
Earnings test - Working while collecting early? FinPlan calculates exactly how much your benefit is reduced and when it's restored
Spousal benefits - Calculates whether you receive more from your own record or as a spouse (up to 50% of worker's PIA), with correct early-claiming reductions
Survivor benefits - Estimates survivor benefits (up to 100% of deceased's benefit) with age-based adjustments from age 60 onward
Household benefit planning - Computes combined benefits for dual-earner couples, accounting for spousal top-ups
Real SSA parameters - Uses actual bend points, taxable earnings caps, and earnings test limits for 2024, 2025, and 2026

Save and Reload Your Plan¶

Your financial plan is saved as a simple file. You can:

Create your plan in one session, save it, and come back later
Update it when things change (got a raise, opened a new account, changed jobs)
Keep different versions (this year vs last year, optimistic vs conservative)

Coming Soon¶

Roth conversion planning - Find the best years to convert traditional retirement money to Roth
Required Minimum Distributions - Know how much you'll have to withdraw from traditional accounts after age 73
State taxes - Add your state's income tax rules on top of federal
Income and expense modeling - Add pensions, rental income, and recurring expenses to your projections
Withdrawal strategies - Which accounts should you pull from first in retirement to minimize taxes?
Web-based dashboard - Visual charts and interactive planning

What FinPlan Will Never Do¶

FinPlan is a calculator, not an advisor. Here's where we draw the line:

No Investment or Stock-Picking Advice¶

FinPlan will never tell you which stocks to buy, when to sell, or how to time the market. It projects growth based on assumptions you provide. It doesn't tell you what assumptions to use.

No Legal Advice¶

FinPlan will never advise on trusts, wills, business structures, or property disputes.

Why? Legal advice must come from a licensed attorney who understands the laws in your state and your personal situation.

No Tax Filing Advice¶

FinPlan will never prepare your tax return, suggest aggressive tax strategies, or guarantee tax outcomes. It uses published IRS rules for projections only.

Why? Filing taxes is the job of a licensed CPA or tax professional who takes responsibility for the accuracy of your return.

No Insurance Advice¶

FinPlan will never recommend specific insurance products or calculate how much coverage you need.

Why? Insurance needs depend on your health, family situation, and risk factors that require professional assessment.

The FinPlan Philosophy¶

Show the range, not a single answer. The future is uncertain. FinPlan shows you the spread of possible outcomes so you can plan for reality, not a fantasy.

Projection, not prescription. FinPlan gives you the numbers. What you do with them is your choice - ideally with help from qualified professionals when the stakes are high.

No black boxes. Every tax bracket comes from the IRS. Every return assumption is explicit. You can trace any number back to its source.

Your data, your machine. No accounts. No subscriptions. No data sharing. Your financial plan belongs to you.

Getting Started¶

FinPlan is available as: - An MCP server for AI assistant integration - A website (coming soon)

See the Agent Setup Guide for connecting FinPlan to your AI assistant.