Free Online Calculators
Everyday calculators that give you instant, accurate answers — right in your browser. No app downloads, no sign-up, completely free.
All Calculators
Age Calculator
Calculate your exact age in years, months, days, hours, minutes, and seconds. Find out how old you are on any date.
Use calculator →BMI Calculator
Calculate your Body Mass Index (BMI) based on your height and weight. Understand your health category instantly.
Use calculator →BMR Calculator
Calculate your Basal Metabolic Rate (BMR) to understand how many calories your body needs at rest.
Use calculator →Body Fat Calculator
Estimate your body fat percentage using various measurement methods. Track your fitness progress.
Use calculator →Army Body Fat Calculator
Calculate your body fat percentage using the Army method. Track your fitness progress.
Use calculator →Calories Calculator
Calculate your daily calorie needs based on age, gender, weight, height, and activity level.
Use calculator →CGPA Calculator
Calculate your Cumulative Grade Point Average (CGPA) from your semester grades and credits.
Use calculator →Discount Calculator
Calculate discounted prices, savings, and final amounts after applying discounts. Perfect for shopping.
Use calculator →Distance Calculator
Calculate the distance between two points on a map using coordinates or addresses.
Use calculator →Electricity Bill Calculator
Estimate your electricity bill based on power consumption, appliance usage, and energy rates.
Use calculator →Fuel Cost Calculator
Calculate fuel costs for your trips based on distance, fuel efficiency, and fuel prices.
Use calculator →GPA Calculator
Calculate your Grade Point Average (GPA) for a semester or academic year. Easy to use for students.
Use calculator →Grade Calculator
Calculate your final grade based on assignments, tests, and exams with weighted percentages.
Use calculator →GST Calculator
Calculate GST amounts for any price. Find the GST inclusive and exclusive prices instantly.
Use calculator →Income Tax Calculator
Estimate your income tax liability based on your annual income, deductions, and applicable tax slabs.
Use calculator →Loan EMI Calculator
Calculate your monthly EMI payments for home loans, car loans, or personal loans.
Use calculator →Mortgage Calculator
Calculate your monthly mortgage payments, total interest, and total cost over the loan period.
Use calculator →Ovulation Calculator
Predict your ovulation date and fertile window based on your menstrual cycle.
Use calculator →Percentage Calculator
Calculate percentages easily. Find percentage increases, decreases, and proportions instantly.
Use calculator →Pregnancy Calculator
Calculate your due date, conception date, and track your pregnancy week by week.
Use calculator →Random Number Generator
Generate random numbers between any range. Perfect for games, giveaways, and statistical sampling.
Use calculator →Salary Calculator
Calculate your annual salary, monthly salary, hourly rate, and overtime pay accurately.
Use calculator →Scientific Calculator
A full-featured scientific calculator with trigonometric, logarithmic, and exponential functions.
Use calculator →Speed Calculator
Calculate speed, distance, or time using the standard speed formula. Perfect for travel planning.
Use calculator →VAT Calculator
Calculate VAT amounts, inclusive and exclusive prices, and total VAT for any transaction.
Use calculator →Water Intake Calculator
Calculate your daily water intake based on your weight, activity level, and climate.
Use calculator →Why Use Attachad Calculators?
Simple calculations shouldn't require downloading an app or sitting through ads. Attachad's free online calculators are built to be fast, accurate, and distraction-free — open the page, enter your values, and get your answer in seconds.
Whether you're using the Age Calculator to find out exactly how many days old you are, the BMI Calculator to understand your health, or the Random Number Generator to pick a fair winner for a giveaway, every tool is designed to give you the right answer without any friction.
All calculations happen instantly in your browser. There's nothing to install, no data stored, and no account required — just results.
Popular Calculators
The Age Calculator goes beyond simply telling you how many years old someone is. Enter a date of birth and it returns the exact age broken down into years, months, days, hours, minutes, and seconds. Perfect for birthdays, passports, visas, and medical records.
The BMI Calculator helps you understand your body mass index and health category. Whether you're tracking fitness goals or consulting with a doctor, getting your BMI quickly is valuable.
The Random Number Generator removes human bias entirely by generating a cryptographically random number within any range you specify. Perfect for giveaways, raffles, games, and statistical sampling.
How to Use These Calculators
- 1Choose a calculator: Select the calculator you need from the cards above.
- 2Enter your values: Fill in the required fields — dates, ranges, or other inputs depending on the tool.
- 3Get your result: Results appear instantly or with a single click, clearly labeled and easy to read.
- 4Copy or share: Copy your result to the clipboard or share the page link with a pre-filled state where supported.
Frequently Asked Questions
Are these calculators completely free?
Yes. All calculators on Attachad are 100% free to use with no account required. No hidden charges or usage limits.
Is my data kept private?
All calculations are processed in your browser. No data is sent to our servers, keeping your information private and secure.
What calculators are available?
We offer a wide range of calculators including Age, BMI, BMR, Body Fat, Calories, CGPA, Discount, Distance, Electricity Bill, Fuel Cost, GPA, Grade, GST, Income Tax, Loan EMI, Mortgage, Ovulation, Percentage, Pregnancy, Random Number, Salary, Scientific, Speed, VAT, and Water Intake calculators.
Do these tools work on mobile?
Yes. All calculators are fully responsive and work on any smartphone, tablet, or desktop browser without installing anything.