Free Guides on Health & Finance

Plain-English explanations of the maths behind everyday decisions โ€” each one paired with a free calculator so you can run the numbers yourself.

๐Ÿฉบ Health Guides

โš–๏ธ Health
How to Calculate BMI: Formula, Chart & What It Really Means
The BMI formula step-by-step, the WHO category chart, and an honest look at where the number falls short โ€” especially for athletes and older adults.
6 min read
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๐Ÿ”ฅ Health
How Many Calories Should I Eat Per Day? (TDEE Explained)
Why the "2,000 calories a day" recommendation is almost meaningless for most people, and how to calculate your personal TDEE using the Mifflin-St Jeor equation.
7 min read
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โค๏ธ Health
Heart Rate Training Zones Explained: Zone 2, Fat Burn & VO2 Max
What each of the 5 heart rate zones actually does, why Zone 2 is the most underused by recreational exercisers, and how to find your personal zone boundaries.
7 min read
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๐Ÿ’ง Health
How Much Water Should You Drink Per Day? A Practical Guide
Why "8 glasses a day" is too simple, how body weight and activity change your requirement, and what urine colour actually tells you about hydration.
6 min read
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๐Ÿ’ฐ Finance Guides

๐Ÿ“ˆ Finance
How Compound Interest Works: The Simple Guide With Real Examples
Simple vs compound interest, the formula, the Rule of 72, what happens when you add monthly contributions, and why compound interest on debt is the same force working against you.
7 min read
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๐Ÿ  Finance
How to Pay Off Your Mortgage Faster: 7 Strategies That Actually Work
From biweekly payments to mortgage recasting, with real interest savings calculations for each approach โ€” and an honest look at when early payoff isn't the best use of money.
7 min read
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๐Ÿ–๏ธ Finance
Retirement Planning: How Much Do You Actually Need to Retire?
The 4% rule explained clearly, savings benchmarks by age, how Social Security factors in, and what to do if you're behind where you want to be.
7 min read
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๐Ÿฝ๏ธ General
How Much to Tip: The Complete Tipping Guide for Every Situation
Current US tipping standards across restaurants, hotels, rideshares, salons, and delivery โ€” including when it's genuinely okay not to tip.
6 min read
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