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Browse by category

📈

📈 Investment

CAGR Calculator

Calculate the Compound Annual Growth Rate of any investment — from starting value, endi...

Sharpe Ratio Calculator

Risk-adjusted return for any portfolio.

IRR Calculator

Calculate the Internal Rate of Return of a series of cash flows.

NPV Calculator

Calculate the Net Present Value of any investment or project.

Max Drawdown Calculator

Peak-to-trough decline of a portfolio.

Portfolio Volatility Calculator

Calculate the expected volatility (standard deviation) of a multi-asset portfolio, acco...

Dividend Yield Calculator

Dividend yield, yield on cost, and payout ratio.

401(k) Calculator

Estimate how much your 401(k) will be worth at retirement.

P/E Ratio Calculator

Price-to-earnings ratio and PEG ratio.

Annualised Return Calculator

Convert a total investment return into an annual figure.

Dollar-Cost Averaging Calculator

Calculate how dollar-cost averaging grows your investment over time.

Total Return Calculator

Calculate the total return on any investment including capital gains and dividends rein...

SIP Calculator

Calculate the returns on a Systematic Investment Plan (SIP).

Bond YTM Calculator

Calculate the yield to maturity (YTM) of a bond.

Lump Sum vs SIP Calculator

Compare lump sum investing against a Systematic Investment Plan (SIP/DCA).

Expense Ratio Calculator

Calculate the long-term cost of a fund's expense ratio and compare how different fees a...

Portfolio Rebalancing Calculator

Calculate the trades needed to rebalance your investment portfolio to your target alloc...

Future Value Calculator

Calculate what a sum of money will be worth at a future date.

Present Value Calculator

Calculate the present value of a future sum or series of cash flows.

Investment Growth Calculator

Model how your portfolio grows over time.

💰 Financial

Herfindahl-Hirschman Index Calculator

Calculate HHI market concentration from percentage or decimal market shares.

Mortgage Calculator

Monthly repayment, total interest, and overpayment savings.

Loan Calculator

Monthly payments and total interest on any loan.

Auto Loan Calculator

Work out your car finance payments.

Interest Calculator

Simple and compound interest on any amount.

Compound Interest Calculator

See how compound interest grows your money over time.

Investment Calculator

Project the future value of any investment.

Retirement Calculator

Find out if you're on track for retirement.

Savings Calculator

See how your savings grow with regular deposits.

Amortisation Calculator

Full payment schedule for any loan.

Payment Calculator

Monthly payment for any loan amount and rate.

Mortgage Affordability Calculator

Find out how much you can borrow based on your income, deposit, outgoings, and the lend...

Inflation Calculator

What is your money worth in today's prices?

Mortgage Comparison Calculator

Compare two mortgage products side by side — different rates, fees, terms, and deal types.

Salary Calculator

Convert salary between hourly, monthly, and annual.

Mortgage Overpayment Calculator

See how much interest and time you save by making overpayments on your mortgage.

Income Tax Calculator

Estimate your income tax liability.

Buy-to-Let Calculator

Analyse the financial return on a buy-to-let property.

Sales Tax Calculator

Add or remove sales tax from any price.

Rental Yield Calculator

Calculate the gross and net rental yield for any investment property.

🏠 Everyday

Password Generator

Generate a strong, secure password.

IP Address Checker

See your public IP address, location, ISP, and timezone.

QR Code Generator

Create a QR code for any URL or text.

Coin Flip

Flip a virtual coin to get heads or tails.

GPA Calculator

Calculate your GPA from any set of grades.

Morse Code Translator

Translate text to Morse code and back. Play audio.

Grade Calculator

Overall grade from weighted assignments.

NATO Phonetic Alphabet

Convert text to NATO phonetic alphabet (Alpha, Bravo, Charlie...).

Gravel Calculator

How much gravel do you need for a driveway, path, or drain?

Concrete Calculator

How much concrete do you need?

Square Footage Calculator

Area of any room or space in square feet or metres.

BTU Calculator

Air conditioning BTU for any room size.

Electricity Cost Calculator

Cost to run any appliance.

IP Subnet Calculator

Subnet mask, network address, and host range.

Ohm's Law Calculator

Voltage, current, resistance, and power from Ohm's Law.

Pet Food Portion Calculator (Calories per Cup)

Estimate daily food portions for cats and dogs from weight and activity using RER guidelines.

Wind Chill Calculator

Feels-like temperature from wind and air temperature.

Pet Ideal Weight Range Finder (by Breed)

Find the typical healthy weight range for your dog or cat breed.

Heat Index Calculator

Feels-like temperature from heat and humidity.

Periodic Table Lookup

Search elements by name, symbol, or atomic number.

❤️ Health & Fitness

BMI Calculator

BMI, category, and healthy weight range for your height.

Calorie Calculator

Daily calorie needs based on your goals.

Body Fat Calculator

Estimate your body fat percentage.

BMR Calculator

Basal metabolic rate — calories burned at rest.

Ideal Weight Calculator

Healthy weight range for your height.

Pregnancy Calculator

Due date and pregnancy week from last period.

Due Date Calculator

When is your baby due?

Pace Calculator

Running pace, speed, and finish time.

Calories Burned Calculator

Calories burned for 100+ activities.

Macro Calculator

Daily protein, carb, and fat targets.

Heart Rate Zone Calculator

Calculate your training heart rate zones from your age or measured maximum heart rate.

Ovulation Calculator

Fertile window and ovulation date.

VO2 Max Calculator

Estimate your VO2 max from common field tests (Cooper test, 1.5-mile run, or resting he...

Sleep Calculator

Best times to wake up or go to sleep.

One Rep Max (1RM) Calculator

Calculate your estimated one-repetition maximum for any exercise.

Protein Calculator

Daily protein target for your weight and goals.

Running Pace Calculator

Convert between pace, speed, and finish time for any distance.

BAC Calculator

Estimated blood alcohol content.

Life Expectancy Calculator

Estimate your life expectancy based on your age, sex, country, and lifestyle factors.

Caffeine Calculator

Track caffeine intake and see active levels over time.

🔄 Converters

Area Converter

Convert square measurements between metric, imperial, acres, and hectares.

Color Converter

Convert any color between HEX, RGB, HSL, and HSV/HSB. Live swatch, per-format validation, and quick presets for common web colors.

Celsius to Fahrenheit Converter

Convert Celsius to Fahrenheit and Fahrenheit to Celsius instantly. Bidirectional sync with quick-preset reference points.

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal instantly. Pick a source base, type a value, and read the same number in all four bases.

Kilograms to Pounds Converter

Convert kilograms to pounds and pounds to kilograms instantly. Bidirectional sync with preset reference weights from small packages to large adults.

Length Converter

Convert between metres, kilometres, centimetres, millimetres, inches, feet, yards, miles, nautical miles, and light-years.

Unit Converter

Length, weight, volume, temperature, and more.

Temperature Converter

Celsius, Fahrenheit, and Kelvin.

Length Converter

Convert between km, miles, feet, inches, and more.

Weight Converter

Convert between kg, lbs, stone, and more.

Speed Converter

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

Roman Numeral Converter

Convert between Roman numerals and numbers.

Shoe Size Converter

Convert shoe sizes between US, UK, and EU.

Roman Numerals ↔ Arabic Converter

Convert between Roman numerals and Arabic numbers.

Base64 Encoder / Decoder

Encode or decode Base64 text instantly.

Shoe & Clothing Size Converter

Convert shoe and clothing sizes between US, UK, EU, JP, AU, and more.

URL Encoder / Decoder

Encode or decode URL strings.

Pressure Converter

Convert between Pa, bar, psi, atm, mmHg, and more.

Energy Converter

Convert between energy units — joules, kilojoules, kilowatt-hours, BTUs, calories, kilo...

Tyre Size Calculator

Tyre diameter, circumference, and speedometer error from size codes.

🔢 Math

Degrees to Radians Converter

Convert degrees to radians and radians to degrees instantly. Bidirectional sync with quick-preset reference points.

Calculator

Basic and scientific calculations.

Percentage Calculator

Work out any percentage instantly.

Fraction Calculator

Add, subtract, multiply, and divide fractions.

Standard Deviation Calculator

Mean, variance, and standard deviation for any data set.

Average Calculator

Mean, median, and mode for any list of numbers.

Quadratic Formula Calculator

Solve any quadratic equation step by step.

Probability Calculator

Calculate probability for any event.

Scientific Calculator

Trig, logarithms, powers, and more.

Random Number Generator

Generate random numbers in any range.

Ratio Calculator

Simplify ratios and solve proportions.

Mean / Median / Mode Calculator

Calculate the mean, median, mode, range, variance, and standard deviation of any data set.

Exponent Calculator

Any base raised to any power.

P-Value Calculator

Calculate the p-value from a test statistic (z-score, t-statistic, chi-squared, or F-st...

Area Calculator

Area of any 2D shape.

T-Test Calculator

Perform one-sample, two-sample independent, and paired t-tests.

Volume Calculator

Volume of any 3D shape.

Slope Calculator

Slope, angle, and equation of a line.

Log Calculator

Logarithm in any base.

Circle Calculator

Calculate the area, circumference, diameter, and radius of a circle.

⚛️ Physics

Centripetal Force Calculator

Calculate centripetal force, acceleration, velocity, or radius for circular motion.

Angular Momentum Calculator

Solve L = I·ω (rigid body) or L = m·v·r·sin θ (point mass / orbital). Includes shape presets and verified astrophysical examples.

Acoustic Impedance Calculator

Solve z = ρ·c, Z = ρ·c/A, or the reflection/transmission coefficients R and T at a normal-incidence boundary. Includes a verified material library (air, water, steel, bone, muscle, blood, etc.).

Capillary Action Calculator

Solve Jurin's law h = (2γ·cos θ) / (ρ·g·r) for the capillary rise (or depression) of a liquid in a tube.

Wave Frequency Calculator

Solve the wave equation v = f × λ for frequency, wavelength, or wave speed.

Stefan-Boltzmann Calculator

Solve P = εσAT⁴ for the thermal radiation emitted by a surface, or back-solve for temperature given power.

Projectile Motion Calculator

Solve time of flight, max height, and horizontal range for a projectile launched at speed v₀ and angle θ, from any initial height h₀. Includes trajectory samples and gravity presets.

Gravitational Potential Energy Calculator

Solve PE = mgh near a planetary surface or U = -GMm/r in space; for any variable.

Momentum Calculator

Solve linear momentum p = m × v for momentum, mass, or velocity.

Coulomb's Law Calculator

Calculate electrostatic force between two charges using F = k·q₁q₂/r².

Projectile Motion Calculator

Calculate height, flight time, range, trajectory, required velocity or angle, and target-height crossings.

Work-Energy Theorem Calculator

Calculate work, force, displacement, angle, or kinetic energy using W = F·d·cos θ = ΔKE.

Power Calculator

Solve power, work, time, force, velocity, voltage, current, or power factor across mechanical and electrical modes.

Ohm's Law Calculator (V, I, R, P)

Solve Ohm’s law V = IR and power P = VI for any variable.

Centripetal Force Calculator

Solve centripetal force, mass, velocity, or radius for uniform circular motion.

Free Fall Calculator

Solve free-fall time, final velocity, or fall distance under constant gravity.

Gravitational Force Calculator

Solve Newton’s law of universal gravitation for force, mass, or distance.

Impulse Calculator

Solve impulse, average force, or time interval from the impulse-momentum theorem.

Kinetic Energy Calculator

Solve kinetic energy, mass, or velocity from KE = ½mv².

Potential Energy Calculator

Solve gravitational potential energy, mass, height, or gravity from PE = mgh.

Power Calculator

Solve power, work, or time from P = W/t with mechanical and electrical modes.

Work Done Calculator

Solve work, force, displacement, or angle from W = F·d·cosθ.

∫ Calculus

Derivative Calculator

Enter a function to find its first and second derivative.

Indefinite Integral Calculator

Find the antiderivative of a function.

Definite Integral Calculator

Enter a function and upper and lower bounds to compute the definite integral ∫ₐᵇ f(x) dx.

Limit Calculator

Enter a function and the point x approaches to evaluate the limit.

Quadratic Equation Solver

Solve ax²+bx+c=0 with roots, discriminant, and vertex.

Average Rate of Change Calculator

Enter a function and two x-values to find the average rate of change (AROC) — the slope...

Instantaneous Rate of Change Calculator

Enter a function and an x-value to find the instantaneous rate of change at that point.

Slope of Tangent Line Calculator

Enter a function and a point x = a to find the slope of the tangent line at that point ...

Linear Approximation Calculator

Enter a function, a base point a, and an x-value near a to get the linearisation L(x) a...

Riemann Sum Calculator

Approximate integrals using left, right, or midpoint sums.

Taylor Series Calculator

Expand a function as a Taylor series around any point.

Maclaurin Series Calculator

A Maclaurin series is a Taylor series centred at a = 0.

Chain Rule Calculator

Enter an outer function g and an inner function u(x) to compute d/dx[g(u(x))] = g'(u(x)...

Product Rule Calculator

Enter two functions f(x) and g(x) to compute d/dx[f(x)·g(x)] = f'(x)g(x) + f(x)g'(x).

Quotient Rule Calculator

Enter numerator f(x) and denominator g(x) to differentiate f(x)/g(x).

Implicit Differentiation Calculator

Find dy/dx for implicitly defined curves.

Arc Length Calculator

Enter a function and integration bounds to compute the arc length of the curve y = f(x)...

Area Between Two Curves Calculator

Enter two functions f(x) and g(x) and integration bounds to compute the area between th...

Volume of Revolution Calculator

Rotate y = f(x) about the x-axis or y-axis between x = a and x = b.

Critical Points Calculator

Enter a function to find all critical points (where f'(x) = 0 or f'(x) is undefined) an...

📅 Date & Time

Age Calculator

Your exact age in years, months, and days.

Date Calculator

Days between dates, add or subtract days.

Time Zone Converter

Convert times between any two time zones.

Timer & Stopwatch

Countdown timer and stopwatch in one.

Hours Calculator

Time between two times in hours and minutes.

Hours Between Dates

Calculate total hours and minutes between any two dates and times.

Time Calculator

Add and subtract hours, minutes, and seconds.

Workday Calculator

Count working days between dates or add business days.

Day Counter

How many days until or since a date.

Moon Phase Calculator

Current moon phase, illumination, and upcoming phases.

Wedding Anniversary Calculator

Anniversary gift themes and milestones for any couple.

Leap Year Checker

Is any year a leap year?

Days Until Calculator

Count down the days until any future date.

Day of the Week Calculator

What day of the week was any date?

Business Days Calculator

Calculate the number of working days between two dates, or find a future date a set num...

World Clock

See the current time in any city worldwide.

Meeting Time Zone Planner

meeting time zone planner.

🎮 Games

Word Game

Guess the 5-letter word in 6 tries.

Random Picker

Pick a random winner from any list.

Dice Roller

Roll any number and type of dice.

2048

Slide tiles and combine numbers to reach 2048.

Snake Game

Classic snake game — eat, grow, don't crash.

Minesweeper

Classic Minesweeper — clear the board without hitting a mine.

Hangman

Guess the word before the hangman is complete.

Memory Game

Flip cards and find all matching pairs.

Typing Speed Test

Test your typing speed in words per minute.

Sudoku

Classic 9×9 Sudoku puzzle.

Trivia Quiz

Test your knowledge across science, history, geography, and more.

Roulette Probability Calculator

Odds, house edge, and expected loss for every roulette bet.

Poker Hand Calculator

Identify and rank any 5-card poker hand.

💻 Developer Tools

Random Password Generator

Generate cryptographically secure random passwords with adjustable length, character classes, and ambiguous-character exclusion.

Regex Tester

Test regular expressions with live match highlighting.

Cron Expression Builder

Build and decode cron expressions with next-run times.

JSON Formatter

Format, validate, and minify JSON instantly.

Text Diff Tool

Compare two texts and highlight the differences.

JWT Decoder

Decode and inspect JSON Web Tokens instantly.

Unix Timestamp Converter

Convert Unix timestamps to human dates and back.

UUID Generator

Generate random UUID v4 identifiers instantly.

Hash Generator

Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes.

Text to Binary Converter

Convert text to binary, hex, or decimal and back.

Resistor Colour Code

Decode 4-band and 5-band resistor colour codes.

HTML Minifier

Minify HTML by removing whitespace, comments, and redundant attributes.

LED Resistor Calculator

Correct series resistor value for any LED circuit.

CSS Minifier

Minify CSS files by removing whitespace, comments, and redundant code.

JavaScript Minifier

Minify JavaScript files by removing whitespace, comments, and shortening variable names.

Contrast Ratio Checker

WCAG contrast ratio for any text and background colour.

HTTP Status Code Reference

http status code reference.

Colour Palette Generator

Generate harmonious colour palettes from any base colour.

Cron Expression Generator

cron expression generator.

MD5 Hash Generator

Generate MD5 hash values for any text input.

SHA-256 Hash Generator

Generate SHA-256 hashes for any text or file.

🖼️ Image Tools

Image Compressor

Reduce image file sizes without visible quality loss.

Image Resizer

Resize JPG, PNG, or WebP images to any dimensions.

Image Converter

Convert images between JPG, PNG, and WebP formats.

Image Cropper

Click and drag to select any crop area on your image.

Favicon Generator

Upload any image and generate favicon files at 16×16, 32×32, and 48×48 pixels.

Image to PDF

Convert one or more images into a single PDF.

Colour Picker

Pick a colour and get its HEX, RGB, and HSL values.

SVG to PNG Converter

Convert SVG files to PNG at any resolution.

Image to Text (OCR)

Upload an image or take a photo and extract the text instantly using Tesseract.js, a br...

Background Remover

Remove backgrounds from photos and images using the @imgly/background-removal library.

🌍 Travel & Culture

Travel Customs

Local customs travellers get wrong — top 20 destinations.

Etiquette Rules

The most important etiquette rule in each of the world's top 20 countries.

Tipping Guide

Tipping norms for the world's top 30 destinations.

Essential Travel Phrases

Essential phrases in 25 languages — greetings, thanks, please and goodbye.

🧪 Chemistry

Molarity Calculator

Calculate solution concentration from solute amount and volume.

Osmotic Pressure Calculator

Solve osmotic pressure, molar concentration, or temperature using the van’t Hoff equation π = iMRT.

pH Calculator

Solve pH, pOH, [H⁺], [OH⁻] from any input. Includes acid dilution series and temperature-corrected Kw.

pH Calculator

Calculate pH, pOH, hydrogen-ion concentration, and hydroxide concentration with temperature-corrected water constants.

Henderson–Hasselbalch Calculator

Solve buffer pH from pKa and the conjugate base/acid ratio. Includes Van Slyke buffer capacity.

Beer–Lambert Law Calculator

Solve for absorbance, molar absorptivity, concentration, or path length using A = ε × c × l.

Half-Life Calculator

Solve for half-life, elapsed time, or remaining amount using A(t) = A₀ × (½)^(t / t½).

Ideal Gas Law Calculator (PV = nRT)

Solve the ideal gas law PV = nRT for pressure, volume, moles, or temperature.

Dilution Calculator

Solve dilution problems with C₁V₁ = C₂V₂ for concentration or volume.

Ideal Gas Law Calculator

Solve PV = nRT for pressure, volume, moles, or temperature.

Molar Mass Calculator

Compute molar mass and percent composition from any chemical formula.

Molarity Calculator

Solve molarity, moles, or volume from M = n/V with mass-to-moles conversion.

🔄 Conversion

Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, and Rankine.

Area Converter

Convert between area units: square metres, square feet, square yards, acres, hectares and more.

Energy Converter

Convert between energy units: joules, calories, kilocalories, kilowatt-hours, electronvolts and BTU.

Mass/Weight Converter

Convert between metric and imperial mass units: kilograms, grams, pounds, ounces, stones and tonnes.

Power Converter

Convert between power units: watts, kilowatts, horsepower, BTU/h and kcal/h.

Pressure Converter

Convert between pressure units: pascals, atmospheres, bar, psi, mmHg and torr.

Speed Converter

Convert between speed units: metres/second, km/h, mph, knots and feet/second.

Volume Converter

Convert between volume units: litres, millilitres, cubic metres, US/UK gallons and cubic feet.

🌍 Ecology

Population Growth Calculator

Calculate exponential population growth N = N₀·e^(rt) and solve for any variable.

Logistic Growth Calculator

Calculate population with carrying capacity using the logistic equation N(t) = K / (1 + ((K−N₀)/N₀)·e^(−rt)).

Shannon Diversity Index Calculator

Calculate Shannon diversity, Pielou evenness, richness, and Simpson diversity from species counts.

Soil Texture Calculator

Classify soil from its sand, silt, and clay percentages.

Shannon Diversity Index Calculator

Calculate Shannon-Wiener H, Pielou evenness, species richness, and Simpson diversity from species counts with a row-by-row breakdown.

Population Growth Calculator

Model exponential or logistic population growth and solve for population, time, or growth rate.

🦬 Biology

DNA Molecular Weight Calculator

Compute molecular weight, GC content, melting temperature and OD260 mass for ssDNA, dsDNA and RNA.

Hardy-Weinberg Equilibrium Calculator

Solve p² + 2pq + q² = 1 for any of p, q, p², 2pq, or q². Includes carrier-frequency and population-genetics examples.

Protein Molecular Weight Calculator

Calculate molecular weight from an amino acid sequence using average residue masses.

📊 Statistics

Percentile Calculator

Percentile rank and inverse percentile with six interpolation methods.

Z-Score Calculator

Calculate a z-score from a value, mean, and standard deviation: z = (x − μ) / σ.

Standard Deviation Calculator

Calculate sample or population standard deviation, variance, and mean.

Linear Regression Calculator

Calculate the regression line y = mx + b with slope, intercept and R².

Correlation Coefficient Calculator

Pearson r, Spearman ρ, and Kendall τ for paired data.

Confidence Interval Calculator

Calculate a confidence interval for a mean: CI = x̄ ± z(σ/√n).

Hypothesis Test Calculator

One-proportion z-test and one-sample t-test (or z-test with known σ) for means — test statistic, p-value, critical value, and confidence interval.

Chi-Square Test Calculator

Chi-square test for independence or goodness of fit with observed vs expected frequencies.

Free online tools. No sign-up. No download.

Solved gives you instant answers to everyday questions. From financial calculators to unit converters, word counters to password generators, every tool runs in your browser with no account required.

The site covers 450+ tools across 19 categories including finance, maths, health, science, text utilities, developer tools, and more. Results appear immediately. Nothing is stored, nothing is tracked.