EDUCATION

Understand the decisions behind every calculator.

Plain-language explainers on the career and money topics this site's tools touch: what a number means, why it works the way it does, and what to actually do with it. General information, not personalized advice.

27 articles, each paired with a calculator that runs the numbers.
All guides
Credit card or debit card: what's actually different?
Whose money you're spending, how each protects you from fraud, and why only one of them builds credit.
How do student loans actually work?
What you can borrow, when interest starts, what it costs, and how repayment changed in 2026.
How do you actually start saving for retirement?
What a 401(k) and an IRA really are, why the employer match comes first, and what the 2026 limits let you put in.
Renting or buying: how do you actually decide?
What price-to-rent tells you, what owning costs beyond the payment, and the year buying pulls ahead.
How does a mortgage actually work?
What the payment is made of, why the early years buy almost none of the house, and how PMI and points work.
Where should your cash actually sit?
What a savings account really pays, what FDIC insurance covers, and how many months of expenses to hold.
Is a degree actually worth it?
The earnings gap by education, why finishing matters more than the major, and how to price one specific degree.
What is your total compensation?
Salary is two thirds of it. What the other third is made of, and which parts are worth nothing until they vest.
Which debt do you pay first?
Avalanche against snowball, what that choice is really worth, and the two things that decide the outcome instead.
What does cost of living actually mean?
Why nearly all of the difference between places is one category, and when a raise for moving is really a pay cut.
Why do budgets fail?
What the famous rule assumes, what households actually spend, and why the deciding categories are not the tracked ones.
How much house can you really afford?
The 28/36 rule, and what a typical family can buy in 3,063 counties at today's rates.
What is a good net worth for your age?
Federal Reserve medians by age, and why the average describes almost nobody.
How do you convert a salary to an hourly rate?
Where 2,080 hours comes from, and what overtime and long salaried weeks do to it.
How do you read a pay stub?
Every line in the order it is calculated, with a worked $60,000 paycheck.
How does health insurance work?
Premiums, deductibles, copays and the out-of-pocket maximum, with a worked year of care.
How do you fill out a W-4?
The five steps of the 2026 form, the $2,200 child amount, and why a big refund is not a bonus.
How does a 401(k) match work?
Common match formulas on a $60,000 salary, what the full match costs, and how vesting works.
How big should your emergency fund be?
Three to six months of essentials in dollars, and what the Federal Reserve finds people have.
How do credit card companies actually make money?
Interest, interchange, and fees: where issuer revenue actually comes from, and who ends up paying for your rewards.
How does interest actually work?
Simple versus compound, why the rate and the schedule both matter, and the same math working against you in debt.
How do taxes actually work?
Tax brackets, marginal versus effective rate, and the different kinds of taxes that come out of your paycheck, purchases, and property.
How do credit scores actually work?
What goes into the number, what moves it fastest, and which common advice is outdated or wrong.
How do different asset classes actually work?
Stocks, bonds, cash, real estate, gold, and crypto: what you actually own with each one, and how much risk it carries.
How does buying a car actually work?
Financing, depreciation, leasing, and negotiating: what actually moves the real cost beyond the sticker price.
How does your paycheck actually work?
What federal, state, and FICA withholding actually are, and why your take-home pay is lower than your salary.
What is inflation, and how does it actually work?
What CPI actually measures, why prices don't all rise at the same rate, and the difference between nominal and real value.