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Guides & How-To Articles

Step-by-step tutorials to help you understand calculations

finance7 min read

How to Calculate Income Tax in Pakistan 2025-26 — Slabs, Examples & Filing Guide

Learn how to calculate income tax in Pakistan for salaried persons in 2025-26. Includes updated tax slabs, step-by-step calculation example, FBR IRIS filing process, and freelancer tax tips.

finance7 min read

How to Calculate Gratuity in UAE, Pakistan & India — Formula & Examples

Step-by-step guide to calculating gratuity (end of service benefits) in the UAE, Pakistan and India. Includes formulas, eligibility rules, worked examples and common mistakes to avoid.

health7 min read

How to Calculate Daily Calorie Intake — BMR Formula, TDEE & Examples

Learn how to calculate your daily calorie intake using the Mifflin-St Jeor BMR formula and activity multipliers. Includes step-by-step example and tips for weight loss and weight gain.

health7 min read

How to Calculate Pregnancy Weeks from Last Period — Due Date Guide

Learn how to calculate pregnancy weeks from your last menstrual period using Naegele's Rule. Covers trimesters, irregular periods, IVF due dates, and important weekly milestones.

health7 min read

How to Calculate Ideal Weight for Your Height in kg — Formulas & Chart

Find your ideal weight using Devine, Robinson, Miller and Hamwi formulas. Includes ideal weight by height table, BMI-based range calculation, and tips for achieving a healthy weight.

math6 min read

How to Calculate Percentage Increase — Formula, Examples & Tips

Learn how to calculate percentage increase and decrease with the simple formula ((New - Old) / Old) x 100. Step-by-step examples for salary, price and investment growth.

construction6 min read

How to Calculate Area of a Room — Square Footage Guide with Formulas

Learn how to calculate room area in square feet for flooring, painting and tiling. Covers rectangle, circle and L-shaped rooms with unit conversions and paint coverage tips.

general7 min read

How to Calculate Age Exactly — Chronological Age in Years, Months & Days

Learn how to calculate your exact chronological age from date of birth in years, months and days. Covers official documents, Korean age, age difference and fun age facts.

general6 min read

How to Calculate Discount Percentage Off — Formulas, Stacked Discounts & Tips

Learn how to calculate discount amount, sale price and discount percentage with simple formulas. Includes stacked discount math, mental math tricks and online shopping tips.

health7 min read

How to Calculate Sleep Cycles — Best Bedtime & Wake Time Calculator Guide

Learn how sleep cycles work and calculate your ideal bedtime or wake time using 90-minute cycles. Covers sleep stages, nap timing and sleep hygiene tips for better rest.

finance6 min readFeatured

How to Calculate EMI on a Loan — Formula, Examples & Tips

Learn how to calculate EMI (Equated Monthly Installment) on any loan using the standard formula. Step-by-step guide with examples for home, car and personal loans.

health5 min readFeatured

How to Calculate BMI — Formula, Chart & What Your BMI Means

Learn how to calculate Body Mass Index (BMI) using weight in kg and height in cm. Includes WHO BMI chart, categories and tips for healthy weight management.

finance7 min read

How to Calculate Zakat on Gold in Pakistan — Complete Guide

Step-by-step guide to calculating Zakat on gold, cash and investments in Pakistan. Includes Nisab threshold, Zakat rate and calculation examples in PKR.

education6 min read

How to Calculate GPA on a 4.0 Scale — College & University Guide

Learn how to calculate your GPA on a 4.0 scale for college and university. Covers cumulative GPA, semester GPA, weighted GPA and grade point conversion.

math5 min read

How to Calculate Percentage — 3 Easy Methods with Examples

Learn how to calculate percentage of a number, percentage change and percentage increase or decrease. Simple formulas with worked examples for students and everyday use.

finance6 min read

How to Calculate Compound Interest — Formula & Examples

Understand the compound interest formula A=P(1+r/n)^nt with step-by-step examples. Learn the difference between simple and compound interest and how compounding frequency affects returns.

health5 min read

How to Calculate Body Fat Percentage at Home — Navy Method

Learn how to measure and calculate your body fat percentage at home using the US Navy method. Includes measurement guide, formulas for men and women, and healthy ranges.

construction5 min read

How to Convert Marla to Square Feet in Pakistan — Complete Guide

Learn how to convert marla to square feet, kanal to marla and other Pakistani land measurement units. Includes conversion tables for 5 marla, 10 marla and 1 kanal plots.