How-to guides
Short walkthroughs with worked examples. Each one gives the answer first, then shows the steps.
💰 Loans & EMI (6)
- How EMI is calculated, with a worked exampleLearn the EMI formula step by step, see how each instalment splits into interest and principal, and check a worked example for a ₹10,00,000 loan.Updated 2026-11-13
- How to calculate home loan EMI, with an exampleWork out your home loan EMI step by step, see how tenure and rate change the cost, and check a worked example for a ₹50,00,000 loan at 8.5%.Updated 2026-11-13
- How to calculate car loan EMI and the real costFind your car loan EMI, see how tenure and down payment change the interest, and check a worked example for an ₹8,00,000 loan at 9.5%.Updated 2026-11-13
- How to compare personal loan offers by EMI and costCompare personal loan offers by monthly EMI and total interest, and see how a longer tenure or a higher rate changes what a ₹3,00,000 loan costs.Updated 2026-11-13
- How to save interest by prepaying a loanSee how much interest and time you save by paying extra every month or making a lump-sum prepayment, with worked numbers for a ₹10,00,000 loan.Updated 2026-11-13
- How much loan can I get? Estimate your eligibilityEstimate the loan you can afford from your income and existing EMIs, and see how the FOIR share, rate and tenure change the amount a lender may offer.Updated 2026-11-13
📈 Savings & investing (14)
- SIP vs lumpsum: which suits you, with numbersCompare a monthly SIP and a one-time lumpsum with a worked example, and learn when each one makes sense for your income and risk.Updated 2026-11-13
- How to calculate SIP returns, with a worked exampleLearn how a SIP grows, how to work out its maturity value, and how time and the return you assume change the result, with ₹5,000 a month as the example.Updated 2026-11-13
- How to calculate lumpsum investment returnsWork out what a one-time investment grows to with the lumpsum formula, and see how years and return change ₹1,00,000, with worked numbers.Updated 2026-11-13
- How a step-up SIP works, and how much extra it earnsSee how raising your SIP by a fixed percentage every year grows the final value, with ₹10,000 a month as the worked example.Updated 2026-11-13
- How to plan regular withdrawals with an SWPLearn how a systematic withdrawal plan works, how long ₹50,00,000 lasts at different monthly withdrawals, and how to choose a sustainable amount.Updated 2026-11-13
- How to calculate fixed deposit maturity amountWork out what a fixed deposit pays at maturity with the compound interest formula, and see how the compounding frequency changes a ₹1,00,000 deposit.Updated 2026-11-13
- How to calculate recurring deposit maturityLearn how a recurring deposit grows, how banks compound it quarterly, and what ₹5,000 a month earns over 60 months, with the formula and examples.Updated 2026-11-13
- How to calculate simple interest, with examplesCalculate simple interest with P × R × T ÷ 100, work out the total, the rate or the time, and see how it differs from compound interest.Updated 2026-11-13
- How compound interest works, simple vs compoundUnderstand simple and compound interest with worked numbers: how ₹1,00,000 grows at 10%, and how often interest is added changes the final amount.Updated 2026-11-13
- How to calculate CAGR, with examplesLearn how to calculate compound annual growth rate from a start value, an end value and the years, and how to compare investments fairly with it.Updated 2026-11-13
- How inflation reduces your money, with numbersSee how inflation raises what things cost and lowers what your savings can buy, with ₹1,00,000 and rates of 5%, 6% and 7% over 10 and 20 years.Updated 2026-11-13
- How to plan your retirement corpus step by stepEstimate the retirement corpus you need and the monthly SIP to build it, with a worked example for a 35-year-old spending ₹50,000 a month today.Updated 2026-11-13
- How to calculate PPF maturity, with worked examplesWork out what a Public Provident Fund account grows to, why depositing before the 5th matters, and the limits and rate, with worked examples.Updated 2026-11-14
- How to calculate Sukanya Samriddhi maturityWork out what a Sukanya Samriddhi account grows to after 21 years, with the 15-year deposit period, the limits and the rate, with worked examples.Updated 2026-11-14
🧾 Tax & salary (India) (4)
- Old vs new tax regime: which is cheaper for you?Compare the old and new income tax regimes for tax year 2026-27 with worked examples, the rebate, and how many deductions the old regime needs to win.Updated 2026-11-14
- How to add and remove GST from a price, with examplesAdd GST to a price or take it out of a GST-inclusive price, avoid the common mistake, and see the 5%, 18% and 40% rates with worked examples.Updated 2026-11-14
- How to calculate gratuity with the 15-day formulaCalculate gratuity from your wages and years of service with the 15 days formula under the Code on Social Security, with worked examples and the cap.Updated 2026-11-14
- How to calculate HRA exemption, with the three limitsWork out the tax-free part of your house rent allowance as the least of three limits, with the eight 50% metro cities and worked examples.Updated 2026-11-14
🧮 Everyday maths (9)
- How to calculate percentage: every common caseLearn the five percentage calculations people need most: percent of a number, what percent, percent change, increase and decrease, with simple examples.Updated 2026-11-13
- How to calculate percentage change, up or downCalculate the percentage increase or decrease between two numbers with one formula, and see why a rise and the same fall are not the same percentage.Updated 2026-11-13
- How to calculate a discount and the final priceFind the sale price after a discount, work out what two successive discounts really add up to, and see how much you save, with worked examples.Updated 2026-11-13
- How to calculate profit, loss and marginCalculate profit or loss from a cost and a selling price, find the profit percentage and the margin, and learn why the two percentages differ.Updated 2026-11-13
- How to find the mean, median and mode of numbersFind the average, median and mode of a list of numbers by hand, learn when to use each, and check the results with worked examples.Updated 2026-11-13
- How to simplify a ratio and solve proportionsSimplify a ratio to its lowest terms, find a missing number in an equal ratio, and split an amount in a ratio, with simple worked examples.Updated 2026-11-13
- How to add, subtract, multiply and divide fractionsDo the four operations on fractions step by step, simplify the answer and turn it into a mixed number, with worked examples you can check.Updated 2026-11-13
- How to use the basic calculator: sums, remainders, percentAdd, subtract, multiply, divide, raise to a power, find a remainder or a percent of a number with the basic calculator, with worked examples.Updated 2026-11-13
- How to use the scientific and basic calculatorsType sums with brackets, powers, roots, logs, factorials and trigonometry into the scientific calculator, and use the basic one for two-number sums.Updated 2026-11-13
📅 Dates & time (6)
- How to calculate your exact age in years and daysWork out your age in years, months and days from your date of birth, and find your next birthday, with a worked example and the leap-day rule.Updated 2026-11-13
- How to find the number of days between two datesCount the days, weeks and months between two dates, learn whether the start and end day are included, and see examples for 2026 and a leap year.Updated 2026-11-13
- How to add or subtract days, weeks and months to a dateFind the date that is a number of days, weeks, months or years before or after a start date, and learn how month ends and leap days are handled.Updated 2026-11-13
- How to count working days between two datesCount the Monday to Friday days between two dates, subtract public holidays and see worked examples for January and February 2026.Updated 2026-11-13
- How to calculate time duration and hours workedWork out the hours and minutes between two clock times, handle shifts past midnight, subtract a break and convert to decimal hours for a timesheet.Updated 2026-11-13
- How to count down the days to an exam, trip or eventFind how many days, weeks, hours and minutes are left until a date, and learn how the countdown uses your device clock and counts to the start of the day.Updated 2026-11-13
❤️ Health (7)
- How to calculate BMI and what the result meansCalculate body mass index from your weight and height, read the WHO categories, and learn what BMI can and cannot tell you, with worked examples.Updated 2026-11-13
- How to calculate BMR: the calories you burn at restCalculate your basal metabolic rate with the Mifflin-St Jeor equation, with worked examples for a man and a woman, and learn what the number means.Updated 2026-11-13
- How to calculate your daily calories (TDEE)Estimate the calories you need each day to keep, lose or gain weight by multiplying your BMR by an activity factor, with a worked example.Updated 2026-11-13
- How to estimate body fat with a tape measureEstimate your body fat percentage from neck, waist and height measurements with the U.S. Navy method, and see what the result means.Updated 2026-11-13
- How to find your ideal weight range from heightCompare the Devine and Robinson formulas with the healthy BMI range for your height, with worked examples for a man at 175 cm and a woman at 162 cm.Updated 2026-11-13
- How much water should you drink a day?Estimate your daily water target from your weight and exercise with a simple rule, and see the answer in litres and in glasses, with examples.Updated 2026-11-13
- How a pregnancy due date is calculatedLearn how the due date comes from the first day of your last period using the Naegele rule, how cycle length changes it, and how trimesters are dated.Updated 2026-11-13
🎓 Students (4)
- How to convert CGPA to percentage, with examplesConvert a CGPA out of 10 to a percentage with the CBSE multiplier of 9.5, convert back, and learn why some universities use a different rule.Updated 2026-11-13
- How to calculate GPA from credits and gradesCalculate your GPA by weighting each course’s grade points by its credits, with a worked example and the common 4.0 grade scale.Updated 2026-11-13
- How to calculate your marks percentage and targetWork out your percentage from marks obtained and total marks, and find the marks you need to reach a target such as 90%, with worked examples.Updated 2026-11-13
- How to calculate attendance and the classes you can missCalculate your attendance percentage, how many classes in a row you must attend to reach the required level, and how many you can still miss.Updated 2026-11-13