How money actually works
Explanations of the mechanics — compounding, amortization, marginal rates, inflation — with diagrams, and every figure computed by the same code behind our calculators. No jargon, no folklore, nothing you have to take on trust.
Foundations
The handful of ideas everything else in personal finance is built on.
How compound interest actually works
Why the curve bends late, and why that single fact decides more of your outcome than the return you earn.
7 min readInflation, and what your money is actually worth
A salary that never rises is a salary that falls. How to think in real terms instead of nominal ones.
6 min readThe 50/30/20 rule, and when it breaks
A useful default that fails badly in high-cost cities. What to do instead.
6 min read
Borrowing
What debt actually costs, and how the mechanics work against you or for you.
Where your mortgage payment really goes
Most of an early payment is rent on borrowed money. Here is the split, month by month, and what it means for paying extra.
8 min readThere is no good debt, only cheap debt and expensive debt
A better test than the usual categories: what does this borrowing cost, and what does it buy.
7 min readWhy minimum payments are designed to last
The arithmetic that turns a modest balance into a decade of payments.
5 min readRenting is not throwing money away
Interest, maintenance, taxes, and transaction costs are also money that does not come back.
8 min readWhat a credit score is actually measuring
Five inputs, wildly different weights, and the ones people worry about that barely matter.
7 min readAPR, APY, and interest rate are three different things
The three numbers lenders quote, what each includes, and which one to compare.
5 min read
Taxes
How the US system really works, minus the folklore.
How tax brackets actually work
A raise cannot leave you worse off. The most persistent myth in personal finance, dismantled with the real 2026 brackets.
6 min readRoth or Traditional: it is one comparison, not ten
Your tax rate now against your tax rate later. Everything else is detail.
7 min readThe gap between your salary and your paycheck
Four deductions, one of which most people cannot name, and why the state you live in matters this much.
6 min readHolding for a year changes your tax bill
The single date that separates ordinary income rates from long-term capital gains rates.
6 min read
Investing
Growth, risk, and the arithmetic of long horizons.
The 4% rule, and what it does not promise
Where the number came from, what it assumed, and how to use it without trusting it too far.
8 min readAn employer match is not a bonus, it is your salary
The only guaranteed 50–100% return in finance, and how many people leave it unclaimed.
5 min readBuying at a steady rhythm
Why regular contributions beat waiting for the right moment, and what that actually costs you.
6 min readFees are the silent tax on your investments
One percent a year sounds small. Over thirty years it is not small.
6 min readThe risk that only matters near retirement
Two portfolios with identical average returns, wildly different outcomes, decided by the order they arrived in.
8 min read
Protection
The buffers that stop a bad month becoming a bad decade.
0 more guides are being written. Every published article is reviewed when the underlying figures change — tax brackets, contribution limits, and rate assumptions all move.