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useful tools

Run the numbers.

Three small calculators we built our selves, for the questions our readers ask most. Pick one on the left —everything updates as you type. No accounts, no tracking, just math.

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Choose Calculator
01

Compound interest

What does saving today grow into tomorrow?

02

Annualized return

Turn a total gain into a clean yearly rate(CAGR).

03

Mortgage payment

Monthly principal & interest before tax and insurance.

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Calculator

Compound interest

Project a portfolio that starts with a lump sum and grows with regular monthly contributions, compounding every month.

Starting amount Lump sum today
$
Monthly contribution Added every month
$
Annual return 7.0%
% / yr
Time horizon 20 years
years

FUTURE VALUE

$300,851

From $130,000 put in over 20 years.

Total contributed $130,000
Interest earned $170,851
Growth multiple 2.31×
Starting amount
Contributions
Interest

Assumes monthly compounding and contributions made at the end of each month. Returns are illustrative, not a forecast.

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Calculator

Annualized return

Take a starting value, an ending value and a holding period, and express the whole gain as one clean compound rate per year.

Starting value What you put in
$
Ending value What it's worth now
$
Holding period 6.0 years
years

COMPOUND ANNUAL GROWTH RATE

+11.75%

$25,000 → $48,700 over 6 years.

Total return +94.8%
Absolute gain +$23,700
Doubling time at this rate 6.2 years

CAGR smooths a lumpy journey into a single rate: (End ÷ Start) ^ (1 ÷ years) - 1. It ignores any deposits or withdrawals made along the way.

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Calculator

Mortgage payment

A fixed-rate monthly principal-and-interest figure, plus the lifetime cost of the loan. Property tax and insurance are not included.

Home price Purchase price
$
Down payment 20% · $90,000
%
Interest rate 6.4%
%APR
Loan term Fixed rate

MONTHLY PRINCIPAL & INTEREST

$2,251.82

$360,000 financed at 6.4% over 30 years.

Loan amount $360,000
Total interest over term $450,656
Total of all payments $810,656
Down payment
Financed (loan)

Estimate only. Excludes property tax, homeowners insurance, PMI and HOA dues, which can add meaningfully to the true monthly cost.