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ΣCalcYeti

Guides

Clear, no-jargon explainers for the numbers that come up in everyday life — each one paired with a free calculator so you can put it into practice.

How to Calculate Percentage: 3 Easy Methods

The three percentage calculations that cover almost everything — plus a mental-maths shortcut you'll actually remember.

4 min read

How Compound Interest Works (With Examples)

Why money grows faster the longer you leave it — the one concept behind almost all long-term wealth.

5 min read

How Much House Can You Afford?

The lender's rule of thumb, the factors that really set your budget, and the costs people forget.

5 min read

How to Convert Marks to a Percentage

One formula turns marks into a percentage — plus how to handle several subjects and papers worth different amounts.

3 min read

What Is a Good Debt-to-Income Ratio?

What your DTI actually measures, the bands lenders tend to use, and simple ways to bring it down.

4 min read

How to Calculate BMI and What It Means

The BMI formula, what the categories mean, and the honest limits of what a single number can tell you.

4 min read

How Much Should You Save for Retirement?

Rules of thumb worth knowing, why time beats amount, and how to turn a distant target into this month's saving.

5 min read

Margin vs Markup Explained

Two words, same numbers, very different results — and why mixing them up quietly eats your profit.

4 min read

How to Pay Off Credit Card Debt Faster

Avalanche saves the most money; snowball keeps you motivated. Here's how each works and how to choose.

5 min read

How to Calculate Your Net Worth (and Why It Matters)

One number that captures your whole financial position — and why watching it move matters more than your salary.

4 min read

Understanding Your Daily Calorie Needs (BMR & TDEE)

What BMR and TDEE actually mean, how activity changes the number, and why any estimate is a starting point.

4 min read

How to Calculate a Discount and Sale Price

The quick way to work out any sale price in your head — plus how stacked discounts and tax really add up.

3 min read

How to Calculate Your GPA

How grade points and credit hours combine into a GPA — and how to work out the grades you still need.

4 min read

What Is the 4% Rule (Safe Withdrawal Rate)?

A simple rule for turning a nest egg into annual income — where it came from, and where it wobbles.

5 min read

Should You Refinance Your Mortgage?

When refinancing actually pays off, how to find your break-even point, and the traps that erase the savings.

5 min read