Guides Library
In-depth, plain-language guides on the calculations people search for most, each linked to its calculator.
Understand how loan EMI is calculated with the amortization formula, worked examples, and tips to reduce total interest on any loa
Master percentages with plain explanations: percent of, percent change, discounts, tips and the mistakes almost everyone makes.
Learn how compound interest works with the formula, real examples, the Rule of 72, and why starting early beats investing more.
Convert salary to hourly rate correctly: the 2,080-hour rule, overtime, benefits, freelancing math, and job-offer comparisons.
Understand mortgage payments, amortization, points, PMI and refinancing with plain explanations and real numbers.
Understand Body Mass Index: the formula, categories, why athletes get odd results, and better measures to use alongside it.
Calculate concrete volume in cubic yards, convert to bags, add waste allowance, and order like a pro for slabs, footings and colum
Learn how GPA is calculated from grades and credits, how weighted scales work, and how to compute the grades you need.
Convert length, weight, temperature, volume and more with confidence: key factors, mental shortcuts and costly mistakes to avoid.
Learn how to calculate zakat on wealth at 2.5%: what counts, what to subtract, nisab, and a worked example.
Understand the 4% safe withdrawal rule, how to compute your retirement number, and its limits in plain language.
Compare debt snowball vs avalanche with the math: which clears debt faster, which costs less, and how to choose.
Master every percentage calculation: percent of, percent change, stacked discounts, reversals, margin vs markup and percentage poi
Rent or buy? Compare the true costs with the 5% rule, the price-to-rent ratio, breakeven horizon and a full worked example.
How tax brackets really work: marginal vs effective rates, a worked stacking example, why a raise never shrinks your take-home, an
SIP vs lump sum compared with real numbers: the math, rupee-cost averaging, crash scenarios, and a decision framework for your sit
How credit scores work: the five scoring factors, the real dollar cost of a low score, how utilization is calculated, and the fast
How loan prepayment works: real numbers showing what $200 extra a month saves, lump sums, biweekly payments, and when prepaying is
A complete retirement plan in 7 steps: finding your number, capturing the employer match, automating investing, allocation by age,
Convert currency smartly: mid-market rates vs bank rates, spreads, hidden fees, dynamic currency conversion traps, and when timing