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Money — Explained Simply.

Investing, budgeting, taxes, banking, debt and retirement — explained clearly, with free calculators to run the numbers yourself.

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13 explainers
Bar chart of retirement savings checkpoints from 1x salary at 30 to 10x at 67
Investing

How Much to Save for Retirement by Age: Targets From 30 to 67

How much should you save for retirement at 30, 40, 50 and 60? See common targets by age, 2026 account limits, and…

WhyExplain Editorial Team · 9 min read
Bar diagram of the five FICO score factors and their approximate weights
Money

How to Improve Your Credit Score: 10 Steps That Work

Learn how to improve your credit score with 10 steps that work, from paying on time to lowering card balances, plus what…

WhyExplain Editorial Team · 10 min read
Bar chart comparing Roth and traditional IRA after-tax balances at different retirement tax rates
Investing

Roth vs Traditional IRA: Which Is Better for You in 2026?

Roth vs traditional IRA comes down to when you pay tax: now or in retirement. Compare 2026 limits, income rules, withdrawals and…

WhyExplain Editorial Team · 10 min read
Diagram showing how a credit card APR becomes a daily interest charge
Money

What Is APR? Annual Percentage Rate Explained Simply

APR is the yearly cost of borrowing, including interest and some fees. Learn how it works on credit cards and loans, APR…

WhyExplain Editorial Team · 10 min read
Staircase diagram showing three stages of building an emergency fund
Money

What Is an Emergency Fund? How Much to Save and Where to Keep It

An emergency fund is cash set aside for surprise costs like car repairs or job loss. Learn how much to save, where…

WhyExplain Editorial Team · 10 min read
Diagram comparing when tax is paid in a Roth IRA and a traditional IRA
Investing

What Is a Roth IRA? How It Works, 2026 Limits and Rules

A Roth IRA lets your savings grow tax-free and comes out tax-free in retirement. Learn how it works, the 2026 limits, income…

WhyExplain Editorial Team · 11 min read
What a 401(k) is and how it works, explained by WhyExplain
Investing

What Is a 401(k)? How It Works, 2026 Limits and the Employer Match

A 401(k) is a workplace retirement account that lets you invest part of your pay with tax breaks. See the 2026 limits,…

WhyExplain Editorial Team · 11 min read
What a credit score is and how it works, explained by WhyExplain
Money

What Is a Credit Score? How It Works and How to Improve It

A credit score is a number lenders use to judge how likely you are to repay. Learn what goes into a credit…

WhyExplain Editorial Team · 11 min read
Cover image for Why Are Interest Rates Rising?, a WhyExplain Money explainer, with a rising line on a navy background
Money

Why Are Interest Rates Rising Again? What It Means for Your Money

Central banks are raising interest rates again to fight inflation. Learn why, how a rise reaches your mortgage, savings and debts, and…

WhyExplain Editorial Team · 11 min read
How US federal tax brackets work in 2026, explained by WhyExplain
Money

How Do Tax Brackets Work? US Federal Income Tax Explained

Tax brackets tax each slice of your income at its own rate, so a raise never lowers your take-home pay. See the…

WhyExplain Editorial Team · 11 min read
What an index fund is and how it works, explained by WhyExplain
Investing

What Is an Index Fund? How It Works, What It Costs and the Risks

An index fund buys every company in a market index, so you own the whole market at low cost. Learn how index…

WhyExplain Editorial Team · 11 min read
What inflation is and how it affects your money, explained by WhyExplain
Money

What Is Inflation? Causes, Measures and What It Means for You

Inflation is the general rise in prices that makes each dollar buy less. Learn how it is measured, what causes it, the…

WhyExplain Editorial Team · 11 min read
Cover image for What Is Compound Interest?, a WhyExplain Money and Investing explainer, with a curve that rises faster over time
Investing

What Is Compound Interest? A Simple Explanation With Real Examples

Compound interest is interest on your interest. Learn the formula, see real examples, try the Rule of 72, and find out how…

WhyExplain Editorial Team · 10 min read

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Compound Interest
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