Free Online Calculators for Calories, Grades & Finance
Easy grader, GPA, calorie intake, BMI & mortgage calculators — 50+ free tools. No sign-up, instant results.
Explore Top Calculators
🔢 50+ Free Tools
Calculator Central offers 50+ free online calculators for students, teachers, homeowners, and professionals. Whether you need to calculate your GPA, estimate daily calorie intake, check your BMI by age and gender, figure out mortgage payments with taxes and insurance, or compute overtime pay and percentage differences, our tools deliver instant, accurate results with no sign-up required.
Top Free Online Calculators
Whether you need an easy grader for teachers, a mortgage calculator with taxes, a daily calorie intake estimator, or a percentage calculator — our free tools deliver instant results with no sign-up required.
Easy Grader Calculator
Grade tests instantly — free EZ grader for teachers. Enter total questions to get a complete grading chart.
Open Easy Grader Calculator →GPA Calculator
Find your GPA from letter grades or percentages. Works for college, high school, and middle school students.
Open GPA Calculator →Calorie Intake Calculator
Calculate how many calories you should eat per day based on your age, weight, height, and activity level.
Open Calorie Intake Calculator →Mortgage Calculator with Taxes
Estimate monthly payments including property tax, home insurance, and PMI for a complete cost breakdown.
Open Mortgage Calculator with Taxes →BMI Calculator
Check your body mass index by age and gender. Instantly see if you are underweight, normal, overweight, or obese.
Open BMI Calculator →Percentage Calculator
Calculate percentages, discounts, tax, and markup instantly. Also find percentage difference and growth rate.
Open Percentage Calculator →Browse All Free Calculator Categories
50+ free online calculators across 10 categories — from health & fitness and grade & GPA to financial and business & salary — no sign-up, instant results.
Health, Fitness & Daily Calorie Calculators
Calculate your daily calorie needs, track BMI by age and gender, monitor water intake, and optimize your fitness routine with our target heart rate calculator. Our health calculators give you science-backed estimates in seconds — no sign-up required.
Grade, GPA & Easy Grader Tools for Teachers
Navigating academic requirements can be stressful. Our grade and GPA calculators simplify student life — use the easy grader for quick test scoring, find your GPA from letter grades, or calculate what you need on the final exam to pass.
Mortgage, Loan & Personal Finance Calculators
Plan your financial future with our free mortgage, loan, and personal finance calculators. Estimate monthly payments, see how extra payments reduce interest, and track your debt payoff progress.
Business, Percentage & Age Calculators
Calculate salary and hourly pay, find percentage differences, compute overtime earnings, and track important dates with our birthday countdown. Essential tools for professionals, shoppers, and everyday planning.
Home, DIY, Travel & Environmental Calculators
Estimate materials for home renovation with our flooring and paint calculators, plan trip budgets, and calculate your carbon footprint. Free tools for homeowners, travelers, and eco-conscious individuals.
Frequently Asked Calculator Questions
How do I calculate my GPA with letter grades?
Use our GPA calculator. Enter each course's letter grade (A, B, C, etc.) and credit hours. The calculator converts letter grades to grade points (A=4.0, B=3.0) and divides total grade points by total credits. Also works for weighted grades and cumulative GPA.
How many calories should I eat a day to lose weight?
Your daily calorie needs depend on age, weight, height, gender, and activity level. Our calorie intake calculator uses the Mifflin-St Jeor equation to estimate your maintenance calories, then adjusts for weight loss or muscle gain goals. Most adults need 1,600–3,000 calories per day.
Does the mortgage calculator include taxes and insurance?
Yes. Our mortgage calculator with taxes includes property tax, homeowners insurance, and PMI in the monthly payment estimate. Enter your loan amount, interest rate, tax rate, and insurance cost for a complete PITI payment breakdown.
How do I calculate overtime pay?
Our overtime pay calculator computes time-and-a-half (1.5x) and double-time (2x) rates from your regular hourly wage. Enter your standard rate and overtime hours to see total pay. Also use our salary to hourly calculator to convert annual salary to hourly wage.
How do I calculate percentage difference between two numbers?
Use our percentage difference calculator. Enter the two numbers — the calculator finds the absolute difference divided by the average of both numbers, expressed as a percentage. Also try our discount calculator for shopping deals.
How many days until my birthday?
Enter your birth date in our birthday countdown calculator. It instantly shows the exact number of days remaining until your next birthday. You can also calculate your exact age in years, months, and days or find the age difference between two people.
Frequently Used Free Calculator Tools
How to Find Your GPA
Use our GPA calculator to calculate your grade point average from letter grades or percentages. Works for college, high school, and middle school students. Also try our easy grader calculator for quick test grading.
Daily Calorie Intake Calculator
Wondering how many calories you should eat a day? Our calorie intake calculator estimates your daily needs based on age, weight, height, and activity level. Includes options for weight loss, maintenance, and muscle gain.
Mortgage Calculator with Taxes & Insurance
Estimate your full monthly house payment with our mortgage calculator with taxes. Includes property tax, homeowners insurance, and PMI. Also try our loan amortization calculator to see how extra payments reduce interest.
Calculate Pay Hourly & Overtime
Use our salary to hourly pay calculator to convert annual salary to hourly wage. Our overtime pay calculator helps you calculate time-and-a-half and double-time rates instantly.
Percentage Difference & Discount Calculators
Calculate the percentage difference between two numbers, find discounts, or compute tax with our percentage difference calculator and discount calculator. Free, instant results.
Birthday Countdown & Age Calculator
Track how many days until your birthday or calculate your exact age with our birthday countdown and birth age calculator. Also find the age difference between two people.