Fast, accurate, and simple calculators you can use every day — no login, no clutter. CalcTools provides free online calculators for finance, time, and conversions. Our tools are fast, accurate, and work directly in your browser without registration.
Our free online Age Calculator helps you quickly determine your precise age in years, months, and days from your date of birth to the current date. Easily find out how old you are or the age of anyone else with just a few clicks.
Our fast and free Temperature Converter allows you to instantly convert values between Celsius, Fahrenheit, and Kelvin scales. Whether for scientific, culinary, or travel purposes, get accurate temperature conversions with ease.
Our free Loan Payment Calculator helps you quickly estimate your monthly loan payments, total interest paid, and amortization schedule. Easily calculate payments for mortgages, auto loans, or personal loans by inputting the principal amount, interest rate, and loan term.
Accurately calculate your Grade Point Average (GPA) for any academic term or cumulative record. Input your grades and credit hours to understand your academic standing and plan for future success. Essential for students, academic advisors, and educators.
A versatile calculator for all your percentage needs, including finding a percentage of a number, percentage change, and more.
Calculate medication dosages accurately based on patient weight, essential for pediatric and critical care.
Tip: Bookmark your most-used tools. We’re building more calculators over time.
CalcTools is continuously expanding with new calculators and converters to support everyday needs in finance, time management, and measurement.