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EMI Calculator
EMI = P × r × (1+r)ⁿ ÷ [(1+r)ⁿ−1]
→ ₹10L at 9% for 20 yrs = ₹8,997/month
<1sResult time
In-browserPrivate maths
35Hubs
Standard formulasPublished, textbook methods
Private by designMost maths runs in your browser
Works everywherePhone, tablet and desktop
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Quick calculators

Answer the seven most-asked questions right here

No need to open another page for a quick answer. For schedules, charts and advanced options, open the full calculator.

EMI calculator

Monthly instalment for a home, car or personal loan.

Monthly EMI
₹8,997
Principal₹10,00,000
Total interest₹11,59,342
Total payment₹21,59,342
Full EMI calculator with schedule →

Results are estimates for general information only — not financial, tax or medical advice. Verify important numbers before acting. Read the disclaimer

35 category hubs · 289 tools

Browse by category

Every hub groups related calculators with short explanations, so you can move from one question to the next without searching again.

FinanceBudgets, interest, savings InvestmentSIP, CAGR, XIRR, returns LoansEMI, amortization, prepay MortgagePayments, refinance, equity TaxIncome tax, GST, TDS SalaryPaycheck, overtime, hike InsuranceLife, health, cover need CryptoProfit, DCA, mining BusinessMargin, break-even, ROI MarketingCAC, LTV, ad budget SEOTraffic, CTR, keyword value CreatorSponsorships, engagement YouTubeRPM, CPM, watch time Social MediaGrowth, reach, posting HealthBMI, BMR, blood pressure Fitness1RM, pace, heart rate NutritionMacros, protein, calories PregnancyDue date, ovulation MathAlgebra, fractions, stats ScienceLab & classroom tools PhysicsForce, energy, motion ChemistryMolarity, pH, gas laws BiologyGenetics, cells, ecology EducationGPA, CGPA, grades ConversionUnits, data, currency ConstructionConcrete, bricks, paint Civil Engg.Structural, highway EngineeringAll engineering tools MechanicalGears, torque, HVAC ElectricalOhm's law, wire size ElectronicsResistors, filters DeveloperSubnet, hash, cron AITokens, API & GPU cost HomeAffordability, moving TravelTrip cost, flights, fuel
See the full calculator directory →Every page on the site

Calculators for every stage of life

Start from who you are

The same questions come up at the same moments in life. Here are the calculators people reach for most at each stage.

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Search by name, filter by category and sort — 289 tools in one place.

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Interactive · The power of compounding

Watch money grow — and see what waiting costs

Move the sliders. The teal line is what a monthly investment could grow to at a steady return; the amber dashed line is the same plan started five years later.

₹10,000
₹500₹1,00,000
12% p.a.
1%20%
25 years
6 yrs40 yrs

Illustration only — assumes a constant return and monthly investing at the start of each month. Real returns vary.

Invested—
Value—
Growth—
Cost of 5-yr delay—
Investment growth chart Value of monthly investments over time compared with the amount invested and a five-year delayed start.
ValueAmount investedStarted 5 years later

—

SIP calculatorCompound interest calculatorRetirement calculator

Learn · Formula library

The formulas behind the answers

Understanding the maths helps you trust a result — and spot when an input is wrong. 19 formulas people use most, each with its variables explained and a worked example.

EMI (loan instalment)

Loans
EMI = P × r × (1+r)ⁿ ÷ [(1+r)ⁿ − 1]

The fixed monthly amount that repays a loan with interest over its tenure. Early EMIs are mostly interest; later ones are mostly principal.

P
loan amount (principal)
r
monthly rate = annual rate ÷ 12 ÷ 100
n
number of monthly instalments
WORKED EXAMPLE
₹10,00,000 at 9% for 20 years → r = 0.0075, n = 240
EMI ≈ ₹8,997 · total paid ≈ ₹21.59 lakh · interest ≈ ₹11.59 lakh
Try it with your numbersEMI Calculator →

SIP future value

Investing
FV = P × [((1+i)ⁿ − 1) ÷ i] × (1+i)

What a fixed monthly investment grows to when each instalment compounds at an expected rate (instalments made at the start of each month).

P
monthly investment
i
monthly return = annual ÷ 12 ÷ 100
n
number of months
WORKED EXAMPLE
₹5,000/month at 12% p.a. for 10 years → i = 0.01, n = 120
Invested ₹6,00,000 → value ≈ ₹11.62 lakh
Try it with your numbersSIP Calculator →

Compound interest

Savings
A = P × (1 + r/n)^(n×t)

Interest that is added back to the principal so it earns interest too. The more often it compounds, the faster it grows.

P
starting amount
r
annual rate as a decimal
n
compounding periods per year
t
years
WORKED EXAMPLE
₹1,00,000 at 8% compounded quarterly for 5 years
A ≈ ₹1,48,595 · interest earned ≈ ₹48,595
Try it with your numbersCompound Interest Calculator →

CAGR (growth rate)

Investing
CAGR = (End ÷ Start)^(1/years) − 1

The steady yearly rate that would take a value from its start to its end. It smooths out ups and downs, so it says nothing about volatility.

End
final value
Start
initial value
years
holding period
WORKED EXAMPLE
₹1,00,000 grows to ₹2,00,000 in 5 years
CAGR = 2^(1/5) − 1 ≈ 14.87% per year
Try it with your numbersCAGR Calculator →

Simple interest

Savings
SI = P × R × T ÷ 100

Interest charged or earned only on the original amount. Common for short loans, some deposits and quick estimates.

P
principal
R
rate % per year
T
time in years
WORKED EXAMPLE
₹50,000 at 6% for 3 years
SI = 50,000 × 6 × 3 ÷ 100 = ₹9,000
Try it with your numbersSimple Interest Calculator →

Future value (lump sum)

Investing
FV = PV × (1 + r)ⁿ

What a one-time amount grows to at a steady annual return. The engine behind lumpsum, FD and long-term goal planning.

PV
amount invested today
r
annual return as a decimal
n
number of years
WORKED EXAMPLE
₹1,00,000 at 10% for 10 years
FV = 1,00,000 × 1.1¹⁰ ≈ ₹2,59,374
Try it with your numbersFuture Value Calculator →

Inflation-adjusted value

Economy
Real value = Amount ÷ (1 + i)ⁿ

How much a future amount is worth in today's money. Use it to check whether a goal or a return keeps up with rising prices.

i
yearly inflation as a decimal
n
number of years
WORKED EXAMPLE
₹1,00,000 in 10 years at 6% inflation
1,00,000 ÷ 1.06¹⁰ ≈ ₹55,839 in today's money
Try it with your numbersInflation Calculator →

Explainers · Numbers in context

Three things the calculators can't tell you on their own

A result is just a number until you know what drives it. These short explainers use real figures to show what's going on underneath.

Loans

Why your EMI is mostly interest at first

An EMI stays the same every month, but its mix changes. Interest is charged on the balance you still owe, so in the early years most of each payment goes to interest and only a little reduces the loan.

Interest and principal paid per year on a ₹10 lakh loan at 9% for 20 years
₹10 L · 9% · 20 yrsInterest paidPrincipal repaidInterest share
Year 1₹89,240₹18,727 83%
Year 5₹81,161₹26,806 75%
Year 10₹65,997₹41,970 61%
Year 15₹42,256₹65,711 39%
Year 20₹5,084₹1,02,883 5%

Takeaway: half the loan is still outstanding after 13 years, which is why part-prepayments made early save the most interest.

EMI calculator →Prepayment calculator →Amortization schedule →
Health

BMI for Indians: why the cut-offs are lower

Studies found that people of South Asian origin tend to carry more body fat — and face higher risk of diabetes and heart disease — at the same BMI as many other populations. So lower action points are used.

BMI categories: WHO international versus Indian consensus guidelines
CategoryWHO internationalIndian guidelines (2009)
Normal18.5 – 24.918.0 – 22.9
Overweight25.0 – 29.923.0 – 24.9
Obese30 +25 +

Takeaway: a BMI of 24 is “normal” on the WHO scale but “overweight” under Indian guidelines. Waist size adds useful context — discuss your numbers with a doctor.

BMI calculator →Waist-to-height ratio →Body fat →
Money

What ₹1 lakh is really worth over time

Inflation quietly shrinks what money can buy. At 6% a year, prices roughly double every 12 years — so savings that earn less than inflation lose value even as the balance grows.

Effect of 6% inflation on ₹1 lakh
At 6% inflation, after₹1 lakh buys what costs todayWhat costs ₹1 lakh today will cost
5 years₹74,726₹1,33,823
10 years₹55,839₹1,79,085
20 years₹31,180₹3,20,714
30 years₹17,411₹5,74,349

Takeaway: plan long-term goals in future rupees, and compare returns after inflation and tax.

Inflation calculator →Retirement calculator →SIP calculator →

Compare · Indian savings & investments

FD vs RD vs PPF vs SIP vs gold — at a glance

Which calculator you need depends on where your money goes. Here's how the most common options differ on returns, risk, access and tax.

Comparison of common Indian savings and investment options
OptionHow it worksReturnsRiskAccess to moneyTax (India)Tool
Fixed Deposit (FD)Lump sum at a rate fixed when you bookFixed, known in advanceLowPremature withdrawal usually allowed with a penaltyInterest taxed at your slab rate; TDS may applyCalculate →
Recurring Deposit (RD)Fixed monthly deposit at a fixed rateFixed, known in advanceLowEarly closure usually allowed with a penaltyInterest taxed at your slab rate; TDS may applyCalculate →
PPFGovernment-backed yearly deposits, up to ₹1.5 lakh a yearRate notified by the government each quarterVery low15-year lock-in; partial withdrawals allowed after a few yearsInterest and maturity tax-free; deposit deductible under Sec 80C (old regime)—
SIP in mutual fundsFixed amount invested every monthMarket-linked, not guaranteedModerate–HighRedeem any time (exit load may apply; ELSS has a 3-year lock-in)Capital gains tax on profits when you sellCalculate →
Lumpsum in mutual fundsOne-time investmentMarket-linked, not guaranteedModerate–HighRedeem any time (exit load may apply)Capital gains tax on profits when you sellCalculate →
GoldPhysical gold, gold ETFs or gold fundsMoves with gold pricesModerateGenerally easy to sell; making charges on jewelleryCapital gains tax on profits; GST on purchase of physical goldCalculate →

General information, not investment or tax advice. Rates, limits and tax rules change — check the latest from your bank, fund house or the Income Tax Department, and consider a registered adviser.

Guides by goal

Start from what you're trying to do

Big decisions usually need more than one number. Each path lines up the calculators to use, in order, with a practical tip.

Goal 01

Buying a home

Work out what you can afford before you fall for a house.

  1. Home Affordabilityprice range from income
  2. EMI Calculatormonthly instalment
  3. Home Loan Prepaymentinterest saved by prepaying
  4. Rent vs Buycompare the long-run cost

TipLenders commonly cap total EMIs at roughly 40–50% of take-home pay; staying well below that leaves room for emergencies.

Goal 02

Start investing

Turn a monthly habit into a long-term number.

  1. SIP Calculatormonthly investment growth
  2. Lumpsum Calculatorone-time investment growth
  3. Inflation Calculatorwhat money will really be worth
  4. XIRR Calculatortrue return on irregular cash flows

TipAlways compare returns after inflation and tax — a 7% return with 6% inflation is roughly 1% real growth.

Goal 03

Get fit & eat right

Find your numbers before changing your diet or routine.

  1. BMI Calculatorweight-for-height screen
  2. TDEE Calculatordaily calorie needs
  3. Macro Calculatorprotein, carbs and fat split
  4. Water Intakedaily hydration target

TipThese are estimates for healthy adults. Speak to a doctor or dietitian for medical conditions, pregnancy or big changes.

Goal 04

Run a small business

Know your margins and the sales you need to break even.

  1. Profit Margingross and net margin
  2. Break-evenunits needed to cover costs
  3. Startup Costlaunch budget
  4. ROI Calculatorreturn on any spend

TipMarkup and margin are not the same: a 50% markup on cost is only a 33% margin on price.

Goal 05

Ace your studies

Track grades and plan study time without spreadsheets.

  1. GPA / CGPAgrade point average
  2. Result Percentagemarks to percentage
  3. Attendanceclasses you can miss
  4. Study Timeplan hours per subject

TipCGPA-to-percentage conversion rules differ by university and board — check your institution's official formula.

Common mistakes

Six number traps that cost people money

Most “wrong” answers come from the right formula used the wrong way. Here's how to avoid the classics.

Comparing a flat rate with a reducing rate

✗“10% flat and 10% reducing are the same.”
✓₹1 lakh for 3 years: 10% flat = ₹30,000 interest; 10% reducing ≈ ₹16,162.

Flat rates charge interest on money you've already repaid. Always ask for the reducing-balance rate or the APR.

Check with the EMI calculator →

Confusing percent with percentage points

✗“A rate rising from 8% to 10% is a 2% increase.”
✓It's 2 percentage points — but a 25% increase in the rate.

Percentage points measure the gap between two percentages; percent change measures it relative to the start.

Percentage calculator →

Ignoring inflation

✗“12% returns means my money grows 12% a year.”
✓With 6% inflation, real growth is about 5.7% a year: 1.12 ÷ 1.06 − 1.

Nominal returns tell you how many rupees you'll have; real returns tell you what they'll buy.

Inflation calculator →

Mixing up markup and margin

✗“I add 25% to cost, so my margin is 25%.”
✓A 25% markup on cost is only a 20% margin on the selling price.

Margin = profit ÷ price. Markup = profit ÷ cost. Pricing on the wrong one quietly eats profit.

Profit margin calculator →

Averaging percentage returns

✗“+50% one year and −50% the next averages to 0%.”
✓₹100 → ₹150 → ₹75. You lost 25% overall.

Losses hurt more than equal gains help. Use CAGR to describe growth over several years.

CAGR calculator →

Using an annual rate as a monthly rate

✗“12% interest means 12% each month in the formula.”
✓Monthly rate = 12 ÷ 12 ÷ 100 = 0.01 (1% a month).

Loan and SIP formulas work in months, so annual rates and years must be converted first.

Compound interest calculator →

Rules of thumb

Mental maths shortcuts worth knowing

Quick rules for sanity-checking a number in your head. They are approximations — use a calculator for the exact figure.

72 ÷ rate

Rule of 72

Divide 72 by the annual return to estimate how many years money takes to double.

At 8% → 72 ÷ 8 ≈ 9 years

An approximation; most accurate for rates between about 6% and 10%.

50/30/20

Budget split

A simple starting budget: 50% of take-home pay on needs, 30% on wants, 20% on savings and debt repayment.

₹60,000 → ₹30k / ₹18k / ₹12k

Adjust for high rent cities or large loan repayments.

3–6 months

Emergency fund

Keep 3 to 6 months of essential expenses in a safe, easy-to-access account before investing aggressively.

₹40,000 expenses → ₹1.2–2.4 lakh

Single-income households and freelancers often aim for the higher end.

10–12× income

Life cover

A common rule of thumb for term life insurance cover is 10 to 12 times your annual income, plus outstanding loans.

₹10 lakh income → ₹1–1.2 crore

Needs vary with dependants, debts and existing savings — a needs-based calculation is better.

12 years @ 6%

Inflation halves money

At 6% inflation, prices roughly double — and the value of cash roughly halves — in about 12 years (72 ÷ 6).

₹1 lakh today ≈ ₹55,800 in 10 yrs at 6%

Uses compound inflation; actual inflation varies year to year.

1:6 cement : sand

Brickwork mortar

General brick masonry mortar is commonly mixed at 1:6 (cement:sand), with richer 1:4 mixes for external plaster and exposed work.

1 part cement → 6 parts sand by volume

Follow your structural engineer and local code for load-bearing work.

Did you know?

A short history of calculating

The formulas on this site are centuries in the making.

1557

The equals sign

Welsh mathematician Robert Recorde introduced “=” in The Whetstone of Witte, choosing two parallel lines because “no two things can be more equal”.

1494

The Rule of 72

Luca Pacioli described the rule for estimating doubling time in his Summa de arithmetica — over 500 years before online calculators.

1614

Logarithms

John Napier published logarithms, turning hard multiplication into easier addition. Slide rules built on the idea were used for over 300 years.

1613

Compound interest tables

Richard Witt's Arithmeticall Questions contained some of the earliest printed tables of compound interest.

1830s

Body Mass Index

Belgian statistician Adolphe Quetelet devised the weight-to-height² ratio; the name “Body Mass Index” came later, in 1972.

2017

GST in India

Goods and Services Tax replaced many central and state indirect taxes from 1 July 2017.

calculus

The word “calculate”

It comes from Latin calculus — a small pebble used for counting on an abacus or counting board.

−40°

Where scales meet

Celsius and Fahrenheit read the same number at −40°, the only temperature where that happens.

Cheat sheet

Numbers and conversions to keep handy

The Indian number system and the unit conversions people look up most.

Indian number system

IndianWritten asPower
1 thousand1,00010³
1 lakh1,00,000 = 100 thousand10⁵
10 lakh10,00,000 = 1 million10⁶
1 crore1,00,00,000 = 10 million10⁷
100 crore1,00,00,00,000 = 1 billion10⁹
1 lakh crore1 trillion10¹²

Common conversions

TypeConversion
Length1 inch = 2.54 cm · 1 foot = 30.48 cm · 1 mile = 1.609 km
Weight1 kg = 2.2046 lb · 1 lb = 453.6 g
Area1 sq m = 10.764 sq ft · 1 sq ft = 0.0929 sq m
Land1 acre = 43,560 sq ft = 4,046.86 sq m · 1 hectare = 2.471 acres
Volume1 US gallon = 3.785 L · 1 litre = 1,000 ml
Temperature°F = °C × 9/5 + 32 · °C = (°F − 32) × 5/9
Data1 KiB = 1,024 bytes · 1 KB = 1,000 bytes (decimal)
Energy1 unit of electricity = 1 kWh · 1 kcal = 4.184 kJ
Unit converterArea converterTemperature converterAll converters →

Glossary

Terms you'll meet on our calculators

Plain-English definitions of 24 common finance, health and business terms, each linked to the calculator that uses it.

24 terms
AmortizationLoans
Paying off a loan through scheduled instalments, each split between interest and principal. Calculate →
APRLoans
Annual Percentage Rate — the yearly cost of borrowing, including some fees, expressed as a percentage.
APYSavings
Annual Percentage Yield — the real yearly return after compounding is taken into account. Calculate →
Break-even pointBusiness
The sales volume at which revenue exactly covers fixed and variable costs — zero profit, zero loss. Calculate →
BMIHealth
Body Mass Index — weight in kg divided by height in metres squared; a screening measure, not a diagnosis. Calculate →
BMRHealth
Basal Metabolic Rate — calories your body needs at complete rest to keep vital functions running. Calculate →
CAGRInvesting
Compound Annual Growth Rate — the smoothed yearly growth rate between a start and end value. Calculate →
Capital gainsTax
Profit from selling an asset for more than you paid; often taxed differently for short and long holding periods. Calculate →
CompoundingSavings
Earning returns on previous returns, so growth accelerates over time. Calculate →
CPM / RPMCreators
CPM is what advertisers pay per 1,000 ad impressions; RPM is what a creator actually earns per 1,000 views. Calculate →
Debt-to-incomeLoans
Monthly debt payments divided by gross monthly income — a key ratio lenders check. Calculate →
EMILoans
Equated Monthly Instalment — the fixed monthly payment that repays a loan over its tenure. Calculate →
GSTTax
Goods and Services Tax — India's indirect tax on supply of goods and services, charged in slabs. Calculate →
InflationEconomy
The rate at which general prices rise, reducing what a fixed amount of money can buy. Calculate →
IRRInvesting
Internal Rate of Return — the discount rate that makes the net present value of cash flows zero. Calculate →
LumpsumInvesting
A single, one-time investment, as opposed to regular instalments. Calculate →
Margin vs markupBusiness
Margin is profit as a % of selling price; markup is profit as a % of cost. Calculate →
NPVInvesting
Net Present Value — today's value of future cash flows minus the initial investment. Calculate →
PrincipalLoans
The original amount borrowed or invested, excluding interest. Calculate →
ROIBusiness
Return on Investment — gain from an investment relative to its cost, as a percentage. Calculate →
SIPInvesting
Systematic Investment Plan — investing a fixed amount at regular intervals, usually monthly. Calculate →
Standard deviationMath
How spread out values are around their average; higher means more variability. Calculate →
TDEEHealth
Total Daily Energy Expenditure — BMR multiplied by an activity factor. Calculate →
XIRRInvesting
Extended IRR — annualised return for cash flows that happen on irregular dates. Calculate →

The library · A–Z index

Every calculator on Calculations.one

289 calculators and tools across 23 subject areas, plus 35 category hubs — all free, all in one place.

289Calculators & tools
35Category hubs
19Formulas explained
24Glossary terms

Calculators by subject

  • Health35
  • Investment34
  • Finance29
  • Construction28
  • Math23
  • Business22
  • Conversion18
  • Science13
  • Education12
  • Creator & social12
  • Loans11
  • Tax9
  • Personal8
  • Utilities7
  • Transportation5
  • Real estate5
  • Salary5
  • Time4
  • Developer4
  • Travel2
  • Entertainment1
  • Trading1
  • Information1

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Spotted something off? Tell us with the inputs you used and we will check it. More about us →

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What's the difference between a flat and a reducing interest rate?

A flat rate charges interest on the original loan amount for the whole tenure, while a reducing rate charges interest only on the balance still owed. For the same headline rate, a flat-rate loan costs much more — see the common mistakes section for a worked example.

Why does the SIP calculator show a different value from my fund statement?

The calculator assumes a constant return every month. Real funds go up and down, your SIP dates and NAVs differ, and expense ratios, exit loads and taxes apply. Use XIRR to measure the actual return on your real cash flows.

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