Closing the Gap Between Knowing and Doing
The Problem: Great Advice, No Way to Apply It
I've studied personal finance for years. There are excellent books, seminars, and videos that explain how money works — how to save, invest, and plan for the future. The knowledge is out there.
But here's what I kept running into: the advice is static. A book tells you to "maximize your tax-advantaged accounts before investing in a brokerage." Great. But which accounts, in what order, and how much goes where based on your income and your employer match? That part is left to you — usually with a pen, a napkin, and some optimistic guesswork.
That gap between knowing what to do and actually doing it creates friction. And friction is where good intentions die. You mean to figure out your savings rate, but the math is annoying, so you don't. You know you should rebalance your portfolio, but calculating the trades feels tedious, so you put it off another quarter. The advice exists. The tools to act on it don't — or they're locked behind account signups and financial advisor fees.
The Moment That Started This
October 2025. Open enrollment season.
If you've worked in the U.S., you know the drill. Every fall, you have a narrow window to make decisions that lock in your finances for the entire next year. Which medical plan? A high-deductible plan with an HSA, or a traditional PPO with an FSA? How much to contribute to your HSA? Your 401(k)? And in my case, how much to set aside for my son's daycare — a number that ripples through every other line item in the budget.
I found myself hunched over a yellow notepad, scribbling numbers, crossing them out, recalculating. Trying to figure out the right contribution for each account, making sure the totals added up, checking IRS limits, and hoping I wasn't missing something. It was stressful, and I knew the math wasn't even that hard — there were just too many moving pieces to hold in my head at once.
Then it hit me: I'm not the only person doing this. Millions of people sit down every fall and wrestle with the same decisions, the same scribbled math, the same anxiety about getting the numbers right. And most of them don't have a finance background to fall back on.
I'd spent years learning from books, courses, and videos about how to optimize savings, allocate across tax-advantaged accounts, and plan for the long term. What if I could turn all of that into tools that anyone could use — tools that do the math for you, instantly, so you can focus on the decisions instead of the arithmetic?
That's what motivated me to build this site.
What I Built
I took the most important concepts from what I'd learned and turned each one into an interactive tool. Not a static formula. Not a single-input calculator that spits out one number. Real tools that model your actual situation:
- The Savings Rate Calculator shows exactly where you stand — your savings rate, investment rate, IRS limit warnings, and how each account will grow.
- The Investment Optimizer walks through the tax-efficient order to fill your 401(k), HSA, IRA, and brokerage automatically.
- The Money Flow Analyzer maps every dollar from income to expenses so you can see where your money actually goes.
- The Portfolio Rebalancer tells you exactly what to buy and sell to get back to your target allocation.
- The Net Worth Tracker turns your annual financial checkup into a 5-minute exercise with year-over-year charts.
- The Compound Interest Calculator shows how your money grows — including when your returns start earning more than you contribute.
Everything runs in your browser. No signup. No account linking. No data sent anywhere. You enter your numbers, you get your answers.
The Vision
My vision is simple: anyone should be able to answer three questions in minutes, not hours:
- How am I doing? — Am I saving enough? Is my portfolio balanced?
- Where can I improve? — Am I leaving employer match money on the table? Is my money going where I think it's going?
- What does my future look like? — How will my accounts grow over 10, 20, 30 years?
These are the questions that actually move the needle. Not abstract theory — concrete, personalized answers based on your real numbers.
Time Is the Point
In personal finance, time is your most powerful asset. Compound growth rewards those who start early. But starting requires knowing where you stand, and that's exactly where most people get stuck.
Every week you spend "meaning to figure it out" is a week your money isn't working as hard as it could. These tools exist to make that first step take seconds instead of hours.
The best time to start was years ago. The second best is today — and I built these tools to make today easier.
I hope RunYourNumber provides real value to you.
— Andrew