Financial & Islamic calculator guides
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Percentage Calculator: Complete Guide with Examples
Learn how percentages work with simple formulas and real-life examples. This guide explains percentage calculations, percentage increase, percentage decrease
Islamic Finance — A Fair and Ethical Economic System
Islamic Finance is a financial system based on Islamic principles that promotes honesty, fairness, and ethical business practices. It avoids interest (Riba) and encourages trade, investment
Emergency Fund: How Much You Need and Where to Keep It
How to size an emergency fund, how long it takes to build, where to keep it so it stays safe and accessible, and what counts as a real emergency.
Gross vs Net Pay: Tax Brackets and Your Take-Home Salary
Why your pay slip shows less than your salary, how progressive tax brackets really work, and the difference between marginal and effective tax rates with a worked example.
Credit Card Interest: How It Works and How to Pay It Off
See how credit card interest is calculated, why minimum payments keep you in debt for decades, and how the avalanche and snowball methods compare with real numbers.
How Much Do You Need to Retire? The 4% Rule Explained
Learn how the 4% rule works, how to estimate your retirement number, what you must save each month at different ages, and where the rule falls short.
Mortgage Payment Formula: Calculate It and Pay Less Interest
Learn the mortgage payment formula with a worked example, see where each payment goes, and discover five proven ways to cut the interest you pay over the life of the loan.
How to Calculate Percentages: Increase, Decrease and Discounts
Master the percentage formulas you use every day: percent of a number, percentage change, successive discounts, reverse percentages and the common mistakes to avoid.
Break-Even Analysis: Formula, Examples and How to Use It
Calculate your break-even point in units and revenue, find the sales needed for a profit target, and see how price and cost changes shift the break-even point.
ROI vs CAGR: How to Measure Investment Returns Correctly
ROI shows total gain, CAGR shows the yearly growth rate. Learn the formulas, why they give different answers, and how fees, income and inflation change your real return.
Ideal Weight Formulas Compared: Devine, Robinson, Miller and BMI
Compare the four classic ideal-weight formulas and the BMI healthy range using a worked example, and learn why a range is more useful than a single number.
Dollar-Cost Averaging vs Lump Sum: What the Numbers Show
Should you invest everything at once or spread it over months? Compare dollar-cost averaging and lump-sum investing with worked examples in rising, falling and recovering markets.
Zakat on Business Assets: How to Calculate It Step by Step
How to calculate Zakat on a business: which assets count, how to value inventory and receivables, what to deduct, and a full worked example for a small shop.
Hourly Wage to Annual Salary: How to Convert and Compare Pay
Convert hourly pay to weekly, monthly and annual salary and back again, account for overtime and unpaid time off, and understand why gross pay is not take-home pay.
Metric to Imperial Conversions: A Practical Cheat Sheet
Exact conversion factors for length, weight, volume, temperature, speed and area, with worked examples, kitchen measures and quick mental shortcuts.
How Much to Tip: A Country-by-Country Guide and Easy Math
Tipping customs vary hugely around the world. See typical tip percentages by country and situation, how to calculate and split a tip, and when no tip is expected.
How to Calculate Zakat: A Complete Step-by-Step Guide
A practical six-step method to work out your Zakat: set your Nisab, fix your Zakat date, list zakatable assets, deduct debts, pay 2.5% and give it to the right recipients.
Compound Interest vs Simple Interest: What Is the Difference and Why It Matters
Simple interest grows in a straight line and compound interest in a steepening curve. See the formulas, a 20-year comparison, APR versus APY, and why starting early matters so much.
GPA Around the World: US, UK, European, German and Indian Scales
The US 4.0 scale, UK degree classes, ECTS, German 1.0 to 5.0 and India's 10-point CGPA compared, with the formulas and the right way to convert grades for an application.
BMI for Asian Populations: Why It Can Mislead and What to Use
Standard BMI cut-offs were built mostly on European data. Learn why risk rises at lower BMI in people of Asian descent, which thresholds different countries use, and which measures to add.
Zakat on Savings and Cash: How to Calculate It Correctly
How to work out Zakat on bank balances, savings accounts, cash and digital wallets, including changing balances, short-term debts, interest and joint accounts.
Loan EMI vs Total Cost: What Lenders Don't Tell You Before You Sign
The monthly payment is the easiest number to make attractive and the least informative. Compare tenures, flat versus reducing rates, hidden fees and amortisation before you borrow.
International Money Transfers: Compare the Real Cost
The advertised fee is only part of what you pay. Learn how exchange-rate margins, intermediary fees and card conversion traps work, and how to compare providers properly.
How Much Water Should You Drink a Day? What the Evidence Says
The eight-glasses rule has no solid origin. See what the US and European health authorities actually recommend, what changes your needs, and how to estimate your own.
Final Grade Calculator: Weighted Averages and the Score You Need
Learn the weighted-average formula, work out your current standing mid-semester, and calculate exactly what you need on the final exam to reach your target grade.
Forex Regulation: How to Check Whether a Broker Is Legitimate
There is no single global forex regulator. Learn which authorities license brokers, what protections to expect, how leverage limits differ, and how to verify a licence in five steps.
Rent vs Buy: How to Run the Numbers Before a Mortgage
Use the price-to-rent ratio, the 5% rule and a full worked example to compare the real annual cost of owning and renting, including interest, taxes, maintenance and opportunity cost.
How Prayer Times Are Calculated: The Science Behind Islamic Salah Timings
Prayer times change every day because they are based on the sun's position. This guide explains the exact astronomical calculation behind each of the five Salah times and why apps differ.
Forex Risk Management: The Only Guide You Need as a Beginner
90% of beginner forex traders lose money, and risk management is the primary reason. This guide covers position sizing, stop-loss placement, and the rules that keep traders alive.
BMI vs Body Fat Percentage: Which Measure Actually Tells You If You're Healthy?
BMI is the world's most used health metric but doctors increasingly question it. Body fat percentage tells a different story. Here's how to use both.
Currency Converter Guide: How Exchange Rates Work and How to Get the Best Rate
Exchange rates affect everything from overseas shopping to international investments. This guide explains how they work and how to avoid overpaying.
Student Loan Repayment Guide: Strategies to Pay Off Education Debt Faster
Student loans can follow you for decades. These strategies help you understand your repayment options and reduce the total cost of your education debt.
Technical Analysis Basics: Charts, Patterns, and Indicators Every Trader Should Know
Technical analysis uses price charts and patterns to forecast market direction. Here are the essential tools and concepts that form the foundation of chart-based trading.
Sukuk Explained: What Islamic Bonds Are and How They Work
Sukuk are the Islamic alternative to conventional bonds. Understanding how they are structured helps Muslim investors participate in fixed-income markets without compromising their faith.
Credit Score Guide: What It Is, How It Is Calculated, and How to Improve It
Your credit score affects loans, credit cards, and even rental applications. Understanding what moves it up or down gives you real financial power.
How to Use a Calorie Calculator for Sustainable Weight Loss
Counting calories is one of the most evidence-based approaches to weight management. Learn how to calculate your needs and use the numbers effectively.
Forex Trading for Beginners: A Complete Step-by-Step Guide
Forex is the largest financial market in the world. This guide explains how it works, how trades are made, and what beginners need to know before risking real money.
Islamic Banking vs Conventional Banking: Key Differences Explained
Islamic banking is not just conventional banking with Arabic names. The core principles are fundamentally different. Here is what you need to know.
Beginner's Guide to Stock Market Investing: How to Start Smart
Stock market investing is not as complicated as it seems. This guide covers the essential concepts every new investor needs before putting money to work.
How Inflation Quietly Destroys Your Savings and What to Do About It
Inflation erodes the real value of money sitting idle in a savings account. Understanding how it works helps you protect your wealth.
How to Save Money Every Month: 10 Practical Strategies That Actually Work
Saving money does not require a high income. These 10 proven strategies help anyone build a savings habit regardless of their salary.
How to Calculate Profit and Loss in Trading and Investing
Whether you trade stocks, forex, or crypto, knowing exactly how to calculate your profit and loss is a fundamental skill. Here is everything you need to know.
Murabaha Financing Explained: How to Buy a Home Without Riba
Murabaha is the most widely used Islamic financing structure. This guide explains how it works, how monthly payments are calculated, and how it differs from a conventional mortgage.
Risk to Reward Ratio in Trading: The One Concept That Separates Winners from Losers
Professional traders live by the risk:reward ratio. Learn how to calculate it, why 1:2 is the minimum, and how to apply it to every trade.
How to Calculate Your GPA: Step-by-Step Guide for Students
Confused about GPA calculation? This guide explains the 4.0 scale, grade points, credit hours, and exactly how to calculate semester and cumulative GPA.
Is Forex Trading Halal or Haram? A Balanced Islamic Finance Perspective
The permissibility of forex trading in Islam is debated among scholars. This article presents both views and what makes trading Halal.
Compound Interest: Why Starting Early Can Make You a Millionaire
Compound interest is called the eighth wonder of the world. Here is why it matters and how to use it to build real wealth.
BMI Calculator Guide: What Your BMI Score Really Means for Your Health
Your BMI number is just the start. Learn what it means, its limitations, and what steps to take based on your result.
What is Zakat and How to Calculate It: A Complete Islamic Finance Guide
Zakat is one of the Five Pillars of Islam. This guide explains who must pay, how to calculate your obligation, and what assets are included.