How to Calculate Percentage: Formulas, Shortcuts and Examples
How to calculate percentage the easy way: the formula, X% of Y, what percent one number is of another, reversing a percentage, marks, and mental shortcuts.
Everyday Calculators · 8 guides
Everyday Calculations, Explained Simply
Quick, reliable answers to the sums people look up every day: percentages and discounts, profit margins, BMI, exact age, date differences, time and unit conversions. Each guide shows the formula, a worked example and the common mistake that leads to the wrong answer.
8 articles in Everyday Calculators
Margin vs Markup: The Difference and How to Price Correctly
Margin vs markup explained: both formulas side by side, a margin-to-markup conversion table, pricing for a target margin, and what fees and GST really cost.
CGPA to Percentage: The CBSE Formula and University Rules
Convert CGPA to percentage the right way: CBSE's CGPA × 9.5 rule with worked examples, why universities differ, SGPA vs CGPA, and how to convert back.
Discount Calculation Formula: Find the Real Price and Real Discount
The discount calculation formula both ways, with worked examples: discount %, original price, stacked offers, bank offer caps, GST and which deal is best.
Percentage Increase and Decrease Formula (With Real Examples)
The percentage increase formula with salary-hike and price examples, plus decreases, percentage difference, percentage points and back-to-back changes.
BMI Formula: How to Calculate BMI and What It Means for Indians
The BMI formula in kg and pounds with worked examples, WHO categories beside the lower Indian cut-offs, a healthy weight table by height, and what BMI misses.
How to Calculate Age From Date of Birth (Exact Years, Months, Days)
Calculate age from date of birth in years, months and days: the borrowing method, age as on an exam cut-off date, and Excel DATEDIF formulas we tested.
How to Calculate Hours Worked (Breaks, Night Shifts and Overtime)
How to calculate hours worked: subtract start from end time, deduct breaks, handle shifts past midnight, convert to decimal hours and split out overtime.
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- Percentage CalculatorFind a percentage of a number, and the change between two numbers.Use it free →
- Discount CalculatorWork out the sale price and how much you save.Use it free →
- BMI CalculatorBody Mass Index from your height and weight, with the category.Use it free →
- Age CalculatorYour exact age in years, months and days — plus days to your next birthday.Use it free →
- Unit ConverterConvert length, mass, temperature, area, speed, data and more.Use it free →
- Margin CalculatorWork out margin, markup, profit and the selling price you need.Use it free →