Math & Calculators

From a quick percentage to fractions, prime checks, and significant figures, these calculators give you exact answers without reaching for a spreadsheet. Each one computes the moment you enter a value and shows the working where it helps, so you can trust the result and move on.

Percentage Calculator Free online percentage calculator. Calculate percentages, percentage change, and percentage of a number instantly.

Prime Number Checker Free online prime number checker. Check if any number is prime, find all primes in a range, and list divisors instantly.

Fraction Calculator Free online fraction calculator. Add, subtract, multiply, and divide fractions with step-by-step simplification.

Significant Figures Calculator Free online significant figures calculator. Count and round to significant figures with rules for zeros and decimals.

Number Sorter Sort numbers ascending or descending instantly. Remove duplicates, handle decimals, and copy sorted results.

BMI Calculator Calculate your Body Mass Index (BMI) from height and weight. Supports metric and imperial units with category results.

Tip Calculator Calculate tip and total bill instantly. Choose a tip percentage and split the bill between any number of people.

Discount Calculator Calculate sale price and savings from an original price and discount percentage. See how much you save instantly.

Age Calculator Calculate your exact age in years, months, and days from your date of birth, plus total weeks, days, hours, and next birthday.

Date Difference Calculator Calculate the difference between two dates in days, weeks, months, years, and business days, with an option to include the end day.

Time Duration Calculator Calculate the duration between two times in hours and minutes, with break deduction, decimal hours, and overnight support.

Loan Calculator Calculate your monthly loan payment (EMI), total interest, and total cost from the loan amount, interest rate, and term.

Compound Interest Calculator See how your savings grow with compound interest. Add optional monthly contributions and choose the compounding frequency.

Sales Tax Calculator Add or remove sales tax / VAT from a price. See the net amount, tax, and gross total instantly.

Mortgage Calculator Estimate your monthly mortgage payment including principal, interest, property tax, and home insurance, plus total interest.

Calorie Calculator Free online calorie & TDEE calculator. Find your daily calories to lose, maintain, or gain weight, plus your BMR — metric or imperial.

Macro Calculator Free online macro calculator. Split your daily calories into protein, carbs, and fat with grams for balanced, low-carb, high-protein, or keto diets.

Pace Calculator Free online running pace calculator. Enter your distance and time to get your pace per km and per mile, plus speed in km/h and mph.

Body Fat Calculator Free online body fat calculator using the US Navy method. Estimate your body fat percentage from a few tape measurements — metric or imperial.

Ideal Weight Calculator Free online ideal weight calculator. See your ideal body weight from the Devine, Robinson, Miller, and Hamwi formulas plus a healthy BMI range.

Water Intake Calculator Free online water intake calculator. Find how much water to drink per day based on your body weight and exercise — in liters, ml, cups, and ounces.

Margin & Markup Calculator Free online margin and markup calculator. Enter cost and price to get profit, profit margin %, and markup % — or set a target margin to find the price.

Salary Calculator Free online salary calculator. Convert hourly, daily, weekly, monthly, and annual pay both ways using your hours and days per week.

Simple Interest Calculator Free online simple interest calculator. Enter principal, rate, and time to get the interest earned and the total amount using I = P × r × t.

In-Depth Guides

How to Calculate Your BMI (2026) How Much Water Should You Drink a Day? (2026)