Explainers
Guides
Indexable explainers only — each one maps to a calculator. Short stubs stay off the public list after the quality review.
Is Refinancing Worth It? Break-Even Math Without the Sales Pitch
How to decide if a mortgage refinance saves money after closing costs — using months-to-break-even, not hype.
APR vs Interest Rate: Why Your Monthly Payment Is Not the Whole Cost
A plain-English US guide to APR, fees, and total interest — for personal loans and revolving credit.
Credit Card Interest Drag: How Minimum Payments Stretch Balances
Why minimum payments keep balances alive — and how a fixed payoff plan changes total interest.
Expense Ratios Compound: The Quiet Cost Inside 401(k)s and Funds
How a 0.05% vs 1.00% expense ratio can change retirement balances over 20–30 years.
Paycheck Withholding Basics: Why Gross Is Not Take-Home
A clear US walkthrough of federal, FICA, and state withholding — and how to use a take-home estimator without treating it as a W-4 replacement.
FICA Explained: Social Security and Medicare on Your Stub
What FICA lines mean, why they differ from income tax, and how wage bases shape paycheck friction.
HELOC vs Cash-Out Refinance: Different Friction, Different Math
When interest-only HELOC draws differ from replacing a first mortgage — without a sales pitch.
Bank Fees Checklist: Find the Leak in Your Checking Account
Maintenance, ATM, overdraft-related, wire, and inactivity fees — a practical US checklist.
The Auto Loan APR Trap: Payment Shopping vs Total Cost
How dealers frame monthly payments — and how to recover amount financed, APR, and total interest.
Remittance Fee Math: Fixed Fees vs FX Markup
Why “no fee” transfers can still be expensive — and how to compare providers on all-in cost.
Inflation vs Your Raise: The Paycheck Purchasing-Power Gap
How CPI assumptions interact with raises — and why taxes make “keeping up” harder.