Money Guides
Practical, example-driven guides to everyday money math — written to be genuinely useful, not to rank. Each guide pairs with a free calculator so you can try every formula instantly.
Everyday Math
Guide 01 8 min read
How to Calculate a PercentageLearn three simple percentage formulas with step-by-step examples: finding X% of a number, finding what percent one number is of another, and calculating percent change.Read guide Guide 04 7 min read
How to Calculate a TipMaster restaurant tip math: standard percentages, how to split a bill fairly (including tax and shared items), and quick mental-math methods for any bill.Read guide Shopping Smart
Guide 02 7 min read
How to Calculate a DiscountA plain-English guide to percent-off math: find sale prices, compare two deals, stack coupons correctly, and avoid the traps that make discounts look bigger than they are.Read guide Guide 03 7 min read
How to Calculate Sales TaxUnderstand how sales tax works: the add-tax and remove-tax formulas, pre-tax vs. after-tax prices, rounding, and how to estimate the total before you reach the register.Read guide Growing Money
Guide 05 9 min read
How Compound Interest WorksUnderstand compounding with clear examples: how interest earns interest, why starting early matters so much, and how contributions multiply growth over time.Read guide Guide 06 7 min read
Compound Interest vs. Simple InterestSee exactly how simple and compound interest differ, with side-by-side numbers, formulas, and guidance on when each one applies in real life.Read guide Guide 12 8 min read
How to Calculate Savings Over TimeProject your savings with and without interest: the formulas, a month-by-month method, and realistic examples from emergency funds to long-term goals.Read guide Budgeting
Guide 07 10 min read
How to Build a Simple Monthly BudgetBuild a budget that actually survives contact with real life: a 5-step setup, the 50/30/20 starting point, and fixes for the problems that sink most budgets.Read guide Guide 08 8 min read
How to Track Everyday ExpensesA practical expense-tracking system: what to track, how to categorize without burnout, weekly and monthly reviews, and how to turn data into savings.Read guide Work & Pay
Guide 10 8 min read
How to Calculate Your Hourly PayConvert salary to hourly (and hourly to salary) correctly, account for unpaid time and overtime, and use your true hourly rate to make smarter spending decisions.Read guide Guide 11 7 min read
How to Calculate a Pay RaiseTurn any raise — percent, hourly bump, or new salary — into exact numbers: new pay, monthly and annual gain, and the after-tax, after-inflation reality.Read guide Educational information only. For educational and informational purposes only. This website does not provide personalized financial, investment, tax, or legal advice.
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