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Mortgage, BMI, compound interest, GPA, calorie, age, percentage — fast and accurate calculators for everyday decisions.
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Trusted by millions of users worldwide
Mortgage Calculator
Calculate your monthly mortgage payment, total interest, and amortization schedule. Free m…
BMI Calculator
Calculate your Body Mass Index (BMI) instantly. Supports both metric (kg/cm) and imperial …
Compound Interest Calculator
Calculate compound interest on investments and savings. See how your money grows over time…
Calorie Calculator
Calculate how many calories you need per day to lose weight, maintain, or gain muscle. Bas…
Percentage Calculator
Calculate percentages three ways: find X% of Y, what percent X is of Y, and percentage cha…
Age Calculator
Calculate exact age from date of birth. Find age in years, months, weeks, and days. See ne…
GPA Calculator
Calculate GPA for semester or cumulative grade point average. Supports 4.0 and weighted GP…
Grade Calculator
Calculate your final grade based on weighted assignments. Find what score you need on rema…
Dice Roller
Roll virtual dice online. Supports d4, d6, d8, d10, d12, d20, d100, and custom dice. Roll …
Binary Calculator
Convert binary to decimal, decimal to binary, and perform binary arithmetic. Supports bina…
Salary Calculator
Convert salary to hourly, weekly, monthly pay. Calculate take-home pay after taxes. Free s…
Income Tax Calculator
Estimate your 2025 income tax liability. Calculate federal and state taxes based on filing…
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Accurate Formulas
Each calculator uses verified, up-to-date formulas used by professionals.
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Works Everywhere
Desktop, tablet, mobile — every calculator is fully responsive.
Global Coverage
Tailored for USA, UK, Canada, Australia, and Europe.
Always Free
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💰 Financial Calculators
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CalcProTool offers 148+ free online calculators covering finance, health, math, electrical engineering, unit conversions, and emerging tools for AI cost estimation and sustainability planning. Every calculator is completely free to use, with no registration, no subscription, and no data collection.
Our financial calculators help you make informed decisions about mortgages, loans, investments, and retirement. The mortgage calculator lets you compare loan scenarios and understand amortization schedules. The compound interest calculator shows the power of long-term investing. Our FIRE calculator helps you plan early retirement using the 4% withdrawal rule.
For health and fitness, our BMI calculator, calorie calculator, and macro calculator give you the data you need to reach your goals. All health calculators use clinically validated formulas like Mifflin-St Jeor for BMR and the US Navy method for body fat percentage.
Students love our GPA calculator, grade calculator, and comprehensive math suite. Our binary calculator and hex converter serve computer science students worldwide. The dice roller supports all standard RPG dice for D&D and tabletop games.