calctool.app
A growing collection of free, instant, browser-based calculators. No sign-up, no personal tracking.
Financial Calculators
Browse all →Loan Calculator
Calculate the monthly payment, total interest, and payoff total for any fixed-rate loan or mortgage.
Try it →Compound Interest Calculator
See how savings or investments grow over time with compound interest and optional regular contributions.
Try it →Sales Tax Calculator
Add sales tax to a price to find the tax amount and the total with tax.
Try it →Health & Fitness Calculators
Browse all →BMI Calculator
Calculate your Body Mass Index from height and weight in imperial or metric units, with category ranges.
Try it →Calorie Calculator
Estimate your daily calorie needs (TDEE) from age, sex, weight, height, and activity level using the Mifflin–St Jeor formula.
Try it →Body Fat Calculator
Estimate body fat percentage from body measurements using the U.S. Navy method, in imperial or metric units.
Try it →Math Calculators
Browse all →Percentage Calculator
Find a percentage of a number, what percent one number is of another, and percentage increase or decrease.
Try it →Average Calculator
Calculate the mean, median, mode, range, sum, and count from any list of numbers instantly.
Try it →Fraction Calculator
Add, subtract, multiply, and divide two fractions — results are reduced to lowest terms automatically.
Try it →Everyday Calculators
Browse all →Tip Calculator
Calculate a tip and split the total across any number of people — see per-person and total amounts instantly.
Try it →Age Calculator
Find your exact age in years, months, and days from your date of birth, plus total days lived.
Try it →Date Difference Calculator
Count the number of days, weeks, and months between any two dates — perfect for deadlines and planning.
Try it →Getting started
- Every calculator runs entirely in your browser — nothing is sent to a server.
- Pick a calculator from the menu or the cards above to get started.