Next Dollar

Know precisely whereyour money should go.

Everyone says “just invest.” Next Dollar builds a customized plan for which account gets each dollar first (401(k), IRA, HSA), in the order that saves on taxes and builds long-term wealth.

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No data stored
Takes 5 minutes
Plan + tracker included
or see a real plan first

Pick a situation like yours

See the exact plan it builds, live, before you answer anything.

Chris38 · Product Manager · $120k/yr

Chris earns a solid salary and has opened a handful of accounts over the years, a 401(k) with a match, a Roth IRA, an HSA, without a real plan tying them together. Now he wants someone to lay out the right order to fund them.

Priority order

Start at top. Each line gets part of Chris's monthly money.

Timing

Chris's monthly money checklist

Free

A setup checklist plus a spreadsheet to track each month's progress.

Tax savings

Lower taxes can leave more of Chris's money invested and growing.

This year
$1,614
estimated tax savings
After 30 years
+$777k
after-tax difference

Includes about $337 from HSA payroll savings.

Adjust tax estimate
Federal income tax22%
State + local tax7%
HSA payroll tax7.65%

Chris's plan vs. taxable brokerage

Same monthly money, two paths: Chris's priority plan or one taxable brokerage account. $1,104/mo.

Year 30
Chris's planMoney going inTaxable brokerage
YearYear 30 of 30
Chris's plan$1.8M
Taxable brokerage$1.0M
Estimated difference+$777k

In today's dollars, the plan value at year 30 is about $752k. About $1.2M is investment growth. Chris may also save about $48,420 on tax bills along the way.

See it account by account

Each row shows the account value, then how much of the +$776,875 after-tax difference comes from that account.

Monthly plan total
$1,104/mo
Pre-tax 401(k)Tax-deferred

Skips income tax now at Chris's 29% rate, then grows untaxed until retirement.

Employer match after future tax$413,012
Regular taxable investing$0
Value
$413k
Difference
+$413,014 of difference
Roth 401(k)Tax-free

After-tax going in, then qualified growth and withdrawals can come out tax-free.

Roth dollars after tax-free growth$581,708
Regular taxable investing$474,757
Value
$582k
$500/mo
Difference
+$106,951 of difference
HSATriple tax-free

Deductible going in (saves 36.65%), grows untaxed, and comes out tax-free for medical.

saves ~$1,614/yr in taxes
HSA dollars after tax-free growth$426,973
Tax savings invested$127,715
Regular taxable investing$348,471
Value
$555k
$367/mo
Difference
+$206,216 of difference
Roth IRATax-free

After-tax going in, but every dollar of growth and withdrawal is 100% tax-free.

Roth IRA dollars after tax-free growth$275,729
Regular taxable investing$225,035
Value
$276k
$237/mo
Difference
+$50,694 of difference
Account-by-account total+$776,875

This matches the after-tax difference shown above.

Change the chart
How should Chris invest?

About 6.7% growth a year on average. Picked based on Chris's age.

Projection length
Chris's existing investments

Where it sits matters: Traditional balances are tax-deferred, Roth/HSA balances are tax-free later, and regular accounts are taxed either way.

In pre-tax retirement (Traditional 401k / IRA)$0
In Roth / HSA / tax-free accounts$0
In a regular (taxable) account$0
Expected returns a year6.7% blended
Stocks7%
Bonds4.5%
Cash / savings3.5%
The exact math behind these numbers
Blended return on Chris's mix
65%×7.0% + 25%×7.0% + 8%×4.5% + 2%×3.5%
= 6.7% per year
Customized plan after taxes
Roth/HSA/529 dollars keep the full value. Pre-tax 401(k)/IRA dollars grow first, then reserve 29% for estimated ordinary income tax later. Taxable brokerage dollars are taxed as they grow. Employer match and reinvested tax savings are included.
= $1.8M after 30 years
Taxable brokerage comparison
same $1,104/mo in a taxable brokerage: blended 6.7% − tax drag 0.52%/yr, then 22% capital-gains tax on the price-growth slice of gains at the end.
= $1.0M after 30 years
Savings (cash)
3.5% interest, taxed every year at Chris's 29% rate = 3.5%×(1−0.29)
= 2.5% per year, net
HSA tax savings available to invest
HSA $367/mo × 36.65% tax savings
= +$135/mo available to invest
Tax Chris saves this year
current pre-tax $0/mo × 12 × 29% + current HSA $367/mo × 12 × 36.65%
The chart may use larger later contributions after cash or debt priorities are done.
= $1,614

FAQs

Do you store my answers?

No. We do not store your answers on a server, and there is no account required. Your plan stays in your browser, and the tracker is created on your device when you download it.

What does the tax savings number mean?

It estimates how much more your customized plan may be worth after taxes versus putting the same monthly money into a regular taxable brokerage account.

What if I do not know finance terms?

That is the point. The app explains the order, the monthly amount, and the setup step without expecting you to know the jargon first.