The Cashflow Bake Off

The extra dough decision: pay it down or grow it up?
Step into the kitchen.

You’ve freed up some extra dough—nice work. Meanwhile, you’re deciding what to do with it. Should you pay down a loan? Stack your Roth? Boost your 401(k)? The Bake-Off is a debt pay down vs investment calculator that lets you throw your options in the oven and see which one rises highest over time. Overall, It’s a quick way to explore the possibilities—with clarity, not complexity.

1. Extra Monthly Cash ($)

This is the extra money you have each month (for example, money you saved by cutting a subscription). We’ll compare what happens if you use this money to pay down debt vs. invest it.

2. Time Frame (Years)

How long you plan to keep making these extra payments or contributions? In order to calculate results we assume you do it every month for this many years.

3. Your Two Options

Pick two things to compare—one on the left, one on the right. Then, we’ll ask a few simple questions for each:

Credit Card Pay Down
- Interest Rate (%): the rate you’re paying on your card.
Car Loan Pay Down or Student Loan Pay Down
- Interest Rate (%) and How many years left on your loan.
Mortgage Pay Down or HELOC Pay Down
- Interest Rate (%), Years left, and whether you can write off the interest on your taxes (many people don’t, so you only get the benefit if you itemize).
401(k) Contribution
- Enter your current income (so we can estimate your tax rate),
- Input expected income in retirement (to see what tax you’ll pay later),
- Add your Employer match % (if your boss adds money too),
- Expected annual return (how fast you think it will grow).
Roth IRA Contribution
- Estimated annual return (this grows tax-free).
Taxable Brokerage Contribution
- Your current income (to estimate your tax rate on interest or dividends),
- Expected annual return (we’ll tax only the growth at your long-term rate).
High-Interest Savings Contribution
- Your current income (so we know your tax rate on interest),
- Savings rate % (the rate your bank pays).
529 Plan Contribution
- Expected annual return (this grows tax-free if used for education).

4. Click “Bake It Off”

Once you’ve filled in everything, then hit the button. As can be seen, the tool will show you which option gives you more money—and by how much—at the end of your chosen time frame.

5. Reading the Result

In summary, you’ll see something like:

Option 1 wins by $12,345 over 15 years.
As can be seen, Option 1 will leave you $12,345 ahead after all interest, growth, and taxes.

Why we ask for your income:
We use your income to guess your tax rate so we can show you the after-tax result. Most people don’t know their exact bracket, so just telling us your income lets the calculator do the rest—no APR or tax-jargon needed.

Illustrative Purposes Only: This calculator is provided to help you compare options and is believed to be accurate, but it’s for illustration only.

No Professional Advice: It does not constitute financial, tax, or legal advice. Always do your own research and consult a qualified professional (CPA, CFP, RIA) before making decisions.

Tax Rates Are Estimates: We estimate federal tax brackets from your income and apply a single long-term capital-gains rate. In fact, actual rates vary by state, filing status, deductions, timing, and changing tax law.

Assumptions: Results assume monthly contributions, constant rates of return, fixed loan terms, and no withdrawals. In general, real-world returns, loan balances, and tax rules may differ.

Past Performance ≠ Future Results: Historical averages aren’t guarantees of future performance.

Use at Your Own Risk: You’re responsible for verifying inputs and assumptions. We disclaim all liability arising from use of this tool.

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