Free online calculators for everyday math

Severance Pay Calculator

Calculate your severance pay, pending salary, unused vacation, and statutory bonuses instantly. Get a clear breakdown for 2026.

Unemployment Benefit

Calculate how much unemployment you'll receive in 2026 based on your regulatory base and months worked. Get the exact amount and duration instantly.

Retirement Calculator

Estimate your 2026 retirement pension based on your contribution base and years worked. Get an instant, indicative benefit amount.

Self-employed contribution calculator

Calculate monthly self-employed social security contribution from net income under Spain's 2026 real-income quota system. Estimate cuota autónoma.

Vacation Calculator

Calculate your pending vacation days and their cash value if you don't take them. Get instant results for unused PTO payout.

Overtime Calculator

Calculate the value of your overtime hours based on your salary and work schedule. Find out how much you earn for each extra hour.

Mortgage Calculator

Calculate your monthly mortgage payment using the French amortization system, plus total interest paid over the loan term.

Personal Loan Calculator

Calculate your monthly payment and total interest on a personal loan. Plan your finances with this free, fast and accurate calculator.

Compound Interest Calculator

Calculate how much your money will grow with compound interest, including monthly contributions and reinvested earnings.

VAT Calculator

Calculate VAT on any amount using Spain's rates (21%, 10%, and 4%). Add or remove IVA instantly with this free online VAT calculator.

Percentage Calculator

Calculate percentages online: find what is X% of a number, what percentage Y is of Z, and percentage change. Fast, free, and accurate.

Discount Calculator

Calculate how much you save and the final price after applying any discount. Perfect for shopping sales, deals, and promotional offers.

BMI

Calculate your Body Mass Index (BMI) from your weight and height. See your BMI category and understand your results instantly.

Calorie Calculator

Calculate daily calorie needs and basal metabolic rate using the Harris-Benedict formula. Adjust for age, sex, weight, height, and activity level.

Rule of Three

Quickly calculate the direct rule of three. If A equals B, how much is C? Use our free online calculator for instant results.

Days Between Dates

Calculate the exact number of days between two dates. Ideal for deadlines, vacations, pregnancy, and project planning. Free online date duration calculator.

Age Calculator

Calculate your exact age in years, months, and days from your date of birth. Free online age calculator tool for accurate results in seconds.

Temperature Converter

Free online temperature converter. Convert Celsius, Fahrenheit, and Kelvin instantly. Accurate, fast, and very easy to use.

Weight

Convert between kilograms, pounds, ounces, and grams instantly. Free online weight converter for accurate mass conversions.

Length Converter

Convert between meters, kilometers, miles, feet, inches, and centimeters instantly. Free online length conversion calculator with accurate results.

Speed Converter

Free online speed converter. Instantly convert km/h, mph, m/s, and other units of velocity. Accurate results with a simple, fast interface.

Weighted Average Calculator

Calculate your weighted average instantly. Enter each assignment grade and its weight, then discover the score you need on the final exam to pass.

Hours and Minutes

Calculate the difference between two times, convert hours to minutes, and add durations instantly. Perfect for work shifts, time tracking, and planning.

LCM Calculator

Calculate the least common multiple (LCM) of two or more numbers instantly, with clear examples and step-by-step explanations.

Fraction Calculator

Free online fraction calculator for adding, subtracting, multiplying, and dividing fractions. Get simplified results and step-by-step solutions instantly.

Add Days

Add or subtract days to any date instantly: deadlines, due dates, and deliveries. Enter a date and the number of days to get the exact result.

Word Counter

Count words, characters, sentences, and paragraphs in any text instantly. This free online word counter helps you check text length with no registration required.

Statistics Calculator

Calculate mean, median, mode, variance, and standard deviation instantly. Enter any data set and get accurate statistics with step-by-step results.

Simple Interest Calculator

Calculate simple interest on a loan or investment instantly. Enter principal, annual interest rate, and time in months to get the total amount.

NPV and IRR Calculator

Calculate Net Present Value (NPV) and Internal Rate of Return (IRR) for your investment project with cash flow analysis. Make smarter decisions.

Grade Scale Calculator

Use this grade scale calculator to convert scores to grades on a linear scale. Enter the maximum and minimum scores and grades to generate your scale.

CPS Test

Measure your clicks per second (CPS) with this free online click speed test. Choose a duration and click as fast as you can.

Click Counter

Free online click counter for manual counts. Tap to tally surveys, inventory, attendance, or any counting task. Simple, fast, and accurate.

Number Base Converter

Convert between binary, octal, decimal, and hexadecimal instantly. See simultaneous equivalents for any base with this free online number base converter.

BMR Calculator

Calculate your Basal Metabolic Rate (BMR) with the Mifflin-St Jeor formula and daily calories based on your activity level.

Body Fat Calculator

Calculate your body fat percentage using the US Navy method. Enter your height, neck, waist, and hip measurements for an accurate estimate.

Ovulation

Free ovulation calculator to calculate your ovulation day, fertile window, and next period from the first day of your last menstrual period.

Gasoline cost

Calculate your trip's gasoline expense: distance, fuel consumption, price per liter, and cost per person. Free online calculator.

Currency Converter

Convert between euro, dollar, pound, Mexican peso, Argentine peso, Chilean peso, Colombian peso and Peruvian sol with this free currency converter.

Tip Calculator

Calculate your restaurant tip instantly: percentage, total with tip, and split per person. Quick and easy for any service.

Sueldo neto

Estimate your take-home pay with our free net salary calculator. Federal, state, and FICA taxes are deducted for accurate budgeting.

Números romanos

Free Roman numerals calculator: convert any number to Roman numerals or vice versa. Get instant, accurate results for dates, years, and more.

Generador de contraseñas

Use our free password generator to create strong, random passwords. Customize length, include symbols and numbers, and protect your accounts.

Área (geometría)

Calculate area of squares, rectangles, triangles, circles, and more. Free online geometry area calculator with formulas and examples. Try it now.

Cement Bags

Calculate how many cement bags you need for a slab: length, width, thickness and yield per bag. Instant results.

Paint Needed

Calculate the liters of paint needed for a room: dimensions, doors, windows, coats and coverage. Instant results.

Wallpaper

Calculate how many wallpaper rolls you need for a room: perimeter, height and m² per roll. Includes waste allowance.

Wall Framing

Calculate how many wood or metal studs you need for a framed wall based on length and spacing. Instant results.

Grass Seed

Calculate how many pounds or kilos of grass seed you need for your lawn: area and seeding rate. Instant results.

Cardiac Output

Calculate your cardiac output in L/min with heart rate and stroke volume. HR x SV formula with normal reference range.

eGFR

Estimate your glomerular filtration rate with the Cockcroft-Gault formula: age, weight, creatinine and sex. With kidney function categories.

Fetal Weight

Estimate fetal weight with the Hadlock formula from ultrasound measurements: biparietal diameter, head circumference and femur length.

LLM Cost

Calculate the cost of AI APIs (GPT, Claude, Gemini, DeepSeek): input and output tokens, prompt caching and monthly requests. USD per million tokens.