Every Calculator You Need

39 free online calculators for math, finance, health, conversions, and everyday utility — all in one place.

All Tools39 tools

🎂

Age Calculator

Calculate your exact age in years, months, and days from your date of birth.

Time & Date

📅

Date Difference Calculator

Find the exact difference between two dates in days, weeks, months, and years.

Time & Date

📆

Days Between Dates

Quickly count the number of days between any two dates.

Time & Date

⏱️

Hours Calculator

Calculate the hours and minutes between two times - for shifts, timesheets, and payroll.

Time & Date

⏳

Days Until Calculator

Find out exactly how many days, hours, and minutes until any future date.

Time & Date

Percentage Calculator

Calculate percentages: what is X% of Y, or X is what percent of Y.

Math

⅓

Fraction Calculator

Add, subtract, multiply, or divide fractions with step-by-step results.

Math

🔬

Scientific Calculator

Perform scientific calculations including trigonometry, logarithms, and powers.

Math

√

Square Root Calculator

Calculate the square root of any number, including perfect square check.

Math

Average Calculator

Calculate the mean, median, mode, and range of a set of numbers.

Math

🏦

Loan Payment Calculator

Calculate the monthly payment and total interest for any car, personal, student, or home loan.

Finance

📈

Interest Calculator

Calculate simple and compound interest on your investments or loans.

Finance

🏡

Mortgage Calculator

Calculate monthly mortgage payment, total interest, and amortization details.

Finance

💹

ROI Calculator

Calculate return on investment (ROI) and annualized growth rate (CAGR) of any investment.

Finance

📊

Profit Margin Calculator

Calculate gross and net profit margins from cost and revenue figures.

Finance

⚖️

BMI Calculator

Calculate your Body Mass Index and find out your weight category.

Health

🔥

Calorie Calculator

Calculate your daily calorie needs based on age, weight, height, and activity level.

Health

🏋️

Ideal Weight Calculator

Find your ideal body weight range based on your height and gender.

Health

💧

Water Intake Calculator

Calculate how much water you should drink daily based on your weight and activity.

Health

📏

Length Converter

Convert between meters, kilometers, feet, inches, centimeters, miles, and more.

Converters

⚖️

Weight Converter

Convert between kilograms, pounds, ounces, grams, and stones.

Converters

📐

Area Converter

Convert between square meters, square feet, acres, hectares, and more.

Converters

🧪

Volume Converter

Convert between liters, milliliters, gallons, fluid ounces, cups, and more.

Converters

🚀

Speed Converter

Convert between km/h, mph, m/s, knots, and more speed units.

Converters

🌡️

Temperature Converter

Convert between Celsius, Fahrenheit, and Kelvin temperature scales.

Converters

🔐

Password Generator

Generate strong, random passwords with customizable length and character types.

Digital Tools

🎲

Random Number Generator

Generate random numbers within a specified range with optional quantity.

Digital Tools

📝

Word Counter

Count words, characters, sentences, paragraphs, and estimate reading time.

Digital Tools

🔤

Character Counter

Get detailed character statistics including letters, digits, spaces, and special characters.

Digital Tools

Text Case Converter

Convert text between uppercase, lowercase, title case, sentence case, and more.

Digital Tools

🔑

UUID Generator

Generate random UUID v4 identifiers for use in applications and databases.

Digital Tools

🔐

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 strings back to plain text.

Digital Tools

📐

Square Feet Calculator

Calculate area in square feet from length and width measurements.

Real Estate

🏗️

Construction Cost Estimator

Estimate construction costs based on area, rate per square foot, and additional costs.

Real Estate

🍽️

Tip Calculator

Calculate the tip and per-person split for any bill - 15%, 18%, 20%, or a custom percentage.

Finance

🧾

Sales Tax Calculator

Add or remove US sales tax by state and rate - before-tax price, tax amount, and total.

Finance

🇪🇺

VAT Calculator

Add or remove VAT at any European rate - UK 20%, Germany 19%, France 20%, Ireland 23%, and custom rates.

Finance

🎓

Grade Calculator

Find the grade you need on your final exam, or calculate your current weighted course grade.

Digital Tools

⏰

Hourly to Salary Calculator

Convert hourly pay to yearly salary - or salary to hourly - at 40 hours/week or custom hours.

Finance

Frequently Asked Questions

What calculators does Calcodo offer?

Calcodo offers 39 free online calculators across seven categories: finance (loan payment, tip, sales tax, VAT, ROI, mortgage), health (BMI, calorie, ideal weight with metric and imperial units), math, time and date (hours calculator, days until), converters, digital tools, and real estate.

Are the calculators free to use?

Yes, every calculator on Calcodo is completely free with no sign-up, no limits, and no hidden fees. All calculations run locally in your browser, so your numbers are never sent to or stored on our servers.

Do the calculators work with US units and currencies?

Yes. Health calculators accept pounds and feet/inches as well as kilograms and centimetres, finance calculators support US dollars, euros, and British pounds, and dedicated tools cover US sales tax by state and European VAT rates.

How accurate are the results?

Each calculator uses the standard published formula for its domain - the same amortization formula lenders use, the Mifflin-St Jeor equation for calories, and official VAT rates for the UK and EU. Results are computed with full floating-point precision and rounded for display.

Does Calcodo work on mobile?

Yes, Calcodo is designed mobile-first: every calculator, the search, and category navigation work on phones, tablets, and desktops, with calculators loading instantly and working offline once visited.