Free Online Calculators,
Converters & Tools
Accurate calculators for finance, health, math, business, education and daily life.
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Trending Calculators
View all →Mortgage Calculator
Financial
Free mortgage calculator to estimate your monthly home loan payment, total interest and total cost. Accurate, fast and easy to use.
Open tool →Loan Calculator
Financial
Free loan calculator for personal, auto and student loans. Calculate your monthly payment, total interest and total repayment instantly.
Open tool →EMI Calculator
Financial
Free EMI calculator for home, car and personal loans. Calculate your Equated Monthly Installment, total interest and total payment online.
Open tool →Compound Interest Calculator
Financial
Free compound interest calculator with monthly contributions. See how your money grows with daily, monthly, quarterly or yearly compounding.
Open tool →SIP Calculator
Financial
Free SIP calculator. Estimate the future value of your monthly mutual fund SIP investments with expected returns and total wealth gained.
Open tool →Discount Calculator
Financial
Free discount calculator. Find the sale price and amount saved after a percentage discount, with optional sales tax.
Open tool →Tip Calculator
Financial
Free tip calculator. Calculate the tip amount and split the bill between any number of people instantly.
Open tool →Inflation Calculator
NewFinancial
Free inflation calculator. See how the purchasing power of money changes over time at any average inflation rate.
Open tool →Sales Tax Calculator
NewFinancial
Free sales tax calculator. Add sales tax to a price or extract the tax from a tax-inclusive total at any rate.
Open tool →New Tools
Crypto Profit Calculator
NewFinancial
Free crypto profit calculator. Calculate your cryptocurrency profit or loss, ROI and break-even price including trading fees.
Open tool →Inflation Calculator
NewFinancial
Free inflation calculator. See how the purchasing power of money changes over time at any average inflation rate.
Open tool →Sales Tax Calculator
NewFinancial
Free sales tax calculator. Add sales tax to a price or extract the tax from a tax-inclusive total at any rate.
Open tool →Auto Loan Calculator
NewFinancial
Free auto loan calculator. Estimate your monthly car payment including down payment, trade-in, sales tax and interest.
Open tool →Tattoo Tip Calculator
NewFinancial
Free tattoo tip calculator. Work out a fair tip for your tattoo artist and the total to pay, with the standard 15–25% range built in.
Open tool →Income Tax Calculator
NewFinancial
Free income tax calculator for India's new tax regime (FY 2024-25 / AY 2025-26). Estimate your income tax, rebate, cess and take-home pay.
Open tool →Amortization Calculator
NewFinancial
Free amortization calculator. See your loan's monthly payment, total interest, and how each payment splits between principal and interest over time.
Open tool →FD Calculator
NewFinancial
Free FD calculator. Calculate the maturity amount and interest earned on a fixed deposit with monthly, quarterly or yearly compounding.
Open tool →PPF Calculator
NewFinancial
Free PPF calculator. Estimate the maturity value of your Public Provident Fund from yearly contributions over the 15-year term.
Open tool →CAGR Calculator
NewFinancial
Free CAGR calculator. Find the Compound Annual Growth Rate of an investment from its start value, end value and number of years.
Open tool →Macro Calculator
NewHealth
Free macro calculator. Get your daily protein, carbs and fat targets based on your calories, goal and body — for cutting, maintenance or bulking.
Open tool →Pace Calculator
NewHealth
Free running pace calculator. Find your pace per km and per mile, plus your speed, from a distance and finish time.
Open tool →One Rep Max Calculator
NewHealth
Free one rep max (1RM) calculator. Estimate the most weight you can lift for one rep, with a full percentage table for programming your training.
Open tool →Sleep Calculator
NewHealth
Free sleep calculator. Find the best times to go to bed or wake up based on 90-minute sleep cycles, so you wake up refreshed.
Open tool →Ovulation Calculator
NewHealth
Free ovulation calculator. Find your most fertile days and estimated ovulation date from your last period and cycle length.
Open tool →Hours Calculator
NewDate & Time
Free hours calculator. Add up the hours and minutes between a start and end time, minus breaks — perfect for timesheets and work hours.
Open tool →Graphing Calculator
NewGraphing
Free online graphing calculator. Plot multiple functions, zoom and pan, trace coordinates and export your graph — no download needed.
Open tool →QR Code Generator
NewUtility
Free QR code generator. Create QR codes for URLs, text, WiFi, email and phone numbers. Download as PNG or SVG with custom colors.
Open tool →Mortgage Recast Calculator
NewFinancial
See how a lump-sum payment lowers your monthly mortgage payment after a recast — new payment, monthly savings and total interest saved.
Open tool →Venmo Fee Calculator
NewFinancial
Work out Venmo fees before you send: instant transfer, goods & services and credit-card fees, plus how much to send to receive an exact amount.
Open tool →Dog Lap Day Calculator
NewDate & Time
Find your dog's Lap Day — the exact date your dog becomes 'older' than you in dog years. Enter both birthdays to get the date.
Open tool →Strike Rate Calculator
NewUtility
Cricket strike rate calculator for batting (runs per 100 balls) and bowling (balls per wicket) — instant, with the formulas explained.
Open tool →Vehicle Wrap Pricing Calculator
NewBusiness
Estimate the cost of a car or van wrap: material, labor and design based on vehicle size, coverage and vinyl quality.
Open tool →Popular Converters
All converters →Length Converter
Free length converter. Convert between meters, kilometers, miles, feet, inches, yards, centimeters and more instantly.
Open tool →Weight Converter
Free weight converter. Convert between kilograms, pounds, ounces, grams, stones and tonnes instantly and accurately.
Open tool →Temperature Converter
Free temperature converter. Convert between Celsius, Fahrenheit and Kelvin with exact formulas, instantly.
Open tool →Data Storage Converter
Free data storage converter. Convert between bytes, KB, MB, GB, TB and their binary (KiB, MiB, GiB) counterparts.
Open tool →Latest Articles
All articles →Finance
What Is Inflation and How to Protect Your Money From It
Inflation quietly shrinks your savings every year. Here's how it works, how it's measured, and the practical ways to keep your money's value.
8 min read
Finance
How to Calculate EMI on a Home Loan: Formula, Examples and Smart Prepayment Strategy
Learn exactly how home loan EMI is calculated, how interest and principal split over time, and the prepayment strategies that save the most money.
8 min read
Health
BMI vs. Body Fat Percentage: Which Number Actually Matters for Your Health?
BMI and body fat percentage often disagree. Learn what each measures, where each fails, and which targets are actually worth pursuing.
7 min read
Finance
Compound Interest Explained: Why Starting 10 Years Earlier Beats Investing Twice as Much
A practical guide to compound interest — the formula, the rule of 72, and real examples showing why time beats contribution size.
7 min read
The calculator site that respects your time
Calculator Gi brings together accurate, fast and genuinely free online calculators for every part of life. Plan a mortgage or EMI, estimate your income tax, check your BMI and daily calories, work out a percentage, use the scientific calculator, plot functions on the graphing calculator, or generate QR codes — all in one place, with no sign-ups, no paywalls and no clutter.
Popular tools include the loan calculator, age calculator, compound interest calculator, GPA calculator, SIP calculator and our unit converters. Every tool is built mobile-first and runs instantly in your browser, so results update as you type — and each one explains the formula behind it and how to use it.
We add new calculators continuously. If there is a tool you wish existed, tell us — the best ideas come from the people who use the site every day.
Frequently Asked Questions
▸Are all the calculators really free?
Yes — every calculator, converter and tool on Calculator Gi is completely free, with no sign-up, no download and no usage limits. They work on phones, tablets and desktops.
▸How accurate are the calculators?
Each calculator uses standard, documented formulas — for example the amortization formula for loans, Mifflin-St Jeor for calories and WHO ranges for BMI. Results are estimates for information purposes and not professional financial or medical advice.
▸Do the calculators work offline or on mobile?
All tools are mobile-first and run instantly in your browser. Once a page is loaded, calculations happen on your device — nothing is sent to a server.
▸Is my data stored anywhere?
No. Values you enter are processed locally in your browser and never uploaded. Your privacy is protected by design.