The YoCalc Blog

Plain-English guides to the math behind money, health, and everyday decisions — each paired with a free calculator.

6 min read · Jun 2, 2026

How to Calculate Loan Payments (Step by Step)

Learn how to calculate monthly loan payments by hand with the amortization formula, worked examples, and tips to pay less interest.

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7 min read · Jun 9, 2026

Compound Interest: The Complete Beginner's Guide

What compound interest is, how the formula works, and why starting early beats investing more. Includes worked examples and the Rule of 72.

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5 min read · Jun 16, 2026

Salary to Hourly: What Your Annual Pay Really Means

How to convert an annual salary to an hourly rate, common salary-to-hourly benchmarks, and why your real hourly rate may be lower than you think.

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6 min read · Jun 23, 2026

BMI Explained: What Your Number Means (and What It Doesn't)

How BMI is calculated, what the categories mean, where BMI falls short, and better metrics to track alongside it.

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5 min read · Jun 30, 2026

Tipping in 2026: How Much, When, and the Fast Mental Math

How much to tip at restaurants, bars, and for delivery, how to split a bill fairly, and mental math tricks to calculate any tip in seconds.

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6 min read · Jul 7, 2026

ROI Made Simple: How to Measure Any Investment's Return

How to calculate return on investment, why annualized return (CAGR) matters more than total ROI, and the costs people forget to include.

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7 min read · Jul 10, 2026

Your Mortgage Payment, Decoded: PITI, Rates, and the 30-Year Math

What actually makes up a mortgage payment, how much the interest rate really costs you, and whether a 15- or 30-year term makes sense.

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6 min read · Jul 13, 2026

TDEE Explained: How Many Calories You Actually Burn in a Day

What BMR and TDEE mean, how the Mifflin-St Jeor equation estimates your calorie burn, and how to set a deficit or surplus that actually works.

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5 min read · Jul 16, 2026

Percentage Tricks: Do Almost Any Percent Problem in Your Head

Fast mental math for percentages: the 10% anchor, the reversal trick, percentage change without a calculator, and the mistakes everyone makes.

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6 min read · Jul 19, 2026

The Emergency Fund: How Much, Where to Keep It, How to Build It

How many months of expenses your emergency fund needs, the best accounts to hold it in, and a realistic monthly plan to build it from zero.

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6 min read · Jul 21, 2026

Inflation Explained: Why a Dollar Isn't What It Used to Be

How inflation is measured with the CPI, what it does to savings over time, and practical ways to keep your money's buying power.

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5 min read · Jul 21, 2026

"What Do I Need on My Final?" — The Math, and How to Play It

How to calculate the exact score you need on a final exam, what the weighted-average math means, and smart strategy when the number looks scary.

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6 min read · Jul 22, 2026

Body Fat % vs BMI: Which Number Should You Actually Track?

What body fat percentage tells you that BMI can't, how the Navy tape method works, and healthy body fat ranges for men and women.

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5 min read · Jul 22, 2026

Fractions Made Simple: The Four Operations Without the Fear

A plain-English refresher on fraction arithmetic: common denominators, the flip-and-multiply rule, simplifying with the GCD, and real-life uses.

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