Teachers and students use these free tools for math, timers, generators, and formatting—no sign-up, works in the classroom or at home.
Boost productivity with focused work sessions and timed breaks using the proven Pomodoro Technique
Manage and view events by day, week, or month in a smart calendar interface
Create, edit, save and manage notes directly in your browser.
Measure elapsed time with start, stop, lap, and reset functionalities.
Set custom countdown timers with pause, resume, and audio alerts. Perfect for productivity and time management
Build a smart grocery list with categories, quantities, and mobile-friendly checkoff
Set medication schedules with doses, times, and browser reminders that stay private in your browser
Create simple appointment schedules, available time slots, and customer bookings
Convert between metric, imperial, and other length units including meters, kilometers, inches, feet, miles, and more with real-time conversion
Convert between metric and US customary volume units including mL, L, tsp, tbsp, fl oz, cups, pints, quarts, and gallons with real-time conversion
Convert between metric, imperial, scientific, and other weight units including kilograms, pounds, ounces, grams, and more with precision control
Convert between square meters, square feet, acres, hectares, and other area units for real estate, construction, and land measurement with high precision
Convert between speed units including km/h, mph, m/s, knots, and Mach number. Perfect for road travel, aviation, maritime, and scientific calculations
Convert between torque units including N⋅m, lbf⋅ft, kgf⋅m, dyn⋅cm, and more. Perfect for engineering, automotive, and mechanical applications
Convert between frequency units including Hz, kHz, MHz, GHz, RPM, and more. Perfect for electronics, audio engineering, and scientific calculations
Convert between time units including seconds, minutes, hours, days, weeks, months, and years. Perfect for scheduling, project management, and daily calculations
Convert between data storage units including bits, bytes, KiB, MiB, KB, MB, and more. Perfect for computing, file management, and digital storage calculations
Convert between astronomical distance units including AU, light years, parsecs, kilometers, and miles. Essential for astrophysics, space exploration, and astronomy education.
Convert between molarity units including mol/L, g/L, ppm, and % solution. Essential for chemistry labs, biology research, and pharmaceutical industry.
Convert between force units including newtons, pound-force, dynes, and kilogram-force. Essential for physics, engineering, construction, and automotive applications.
Convert between coordinate systems including decimal degrees, DMS, UTM, and MGRS. Essential for GPS navigation, surveying, mapping, and military applications.
Convert between different hardness scales including Mohs, Rockwell, Vickers, and Brinell. Essential for materials science, metallurgy, and quality control.
Convert between different radiation units including gray, rad, sievert, and rem. Essential for health physics, nuclear science, and medical imaging.
Convert between photon energy units including eV, nm, Hz, and joules. Essential for optics, spectroscopy, and quantum physics.
Convert between different coordinate systems including decimal degrees, DMS, UTM, and MGRS. Essential for GPS navigation, surveying, mapping, and military applications.
Convert between different viscosity units including Pa·s, poise, centipoise, and stokes. Essential for chemical engineering, fluid dynamics, and materials science.
Free MPG calculator: L/100km, km/L, kmpl — US and UK mpg, instant browser results, no sign-up. Automotive, fleet, travel.
Convert between cooking units including cups, tablespoons, grams, ounces, and more. Perfect for recipe conversion, international cooking, and baking.
Convert between logarithmic units including decibels, power ratios, intensity ratios, and more. Essential for audio engineering, signal processing, and acoustics.
Convert between concentration units including mass fraction, mole fraction, ppm, ppb, and more. Essential for chemistry labs, environmental testing, and pharmaceuticals.
Convert between blackbody radiation peak units including temperature, wavelength peak (λmax), and frequency peak (νmax). Essential for astrophysics, thermal physics, and materials science.
Convert between environmental dose units including rad, gray, sievert, and rem. Essential for radiological protection, environmental monitoring, and health physics.
Convert between soil moisture units including volumetric, gravimetric, and saturation percentage. Essential for agriculture, geoscience, soil science, and environmental monitoring.
Convert between pressure units including Pa, bar, atm, PSI, mmHg, and more. Perfect for engineering, physics, chemistry, and everyday applications
Convert between flow rate units including L/s, m³/h, gal/min, cfm, and more. Perfect for HVAC, plumbing, chemical engineering, and irrigation applications
Convert between energy units including joules, calories, kilowatt-hours, BTUs, electron volts, and more. Perfect for physics, engineering, chemistry, and everyday calculations
Convert between power units including watts, kilowatts, horsepower, BTUs per hour, and more. Perfect for electrical engineering, mechanical systems, and power calculations
Convert between angle units including degrees, radians, gradians, and more. Perfect for mathematics, engineering, navigation, and scientific calculations
Convert between density units including kg/m³, lb/ft³, g/cm³, and more. Perfect for physics, chemistry, engineering, and material science calculations
Convert between pH values, hydrogen ion concentrations (H+), hydroxide ion concentrations (OH-), and pOH. Essential for chemistry labs and water quality testing
Convert between g-force, acceleration (m/s², ft/s²), Gal, and related units. Essential for physics, aerospace, and automotive testing
Convert between W/m², mW/cm², BTU/hr·ft², cal/cm²·min, erg/cm²·s, and solar flux units. Essential for optics, solar energy, and environmental science
Convert between heat transfer coefficient units including W/m²·K, BTU/hr·ft²·°F, cal/s·cm²·°C, and more. Perfect for engineering, HVAC, construction, and thermal analysis
Convert between polar coordinates (r, θ), Cartesian coordinates (x, y), and complex numbers. Perfect for mathematics, physics, engineering, and signal processing
Convert between matrix units, determinants, eigenvalues, and normalized values with dimension normalization. Perfect for linear algebra, engineering calculations, and scientific computing
Calculate essential statistical measures including mean, median, mode, standard deviation, variance, and correlation. Perfect for data analysis, research, business analytics, and education
Convert between AWG, SWG, millimeters, and inches for electrical engineering and manufacturing
Convert between pressure, volume, temperature, and moles using the ideal gas law (PV = nRT)
Convert between salinity and total dissolved solids units including PSU, g/kg, mg/L, and more
Convert between dry volume units including bushels, pecks, dry gallons, and more. Perfect for agriculture, grain storage, and bulk material handling
Convert between angular velocity units including rad/s, deg/s, RPM, and more. Essential for mechanical engineering, robotics, and rotational motion analysis
Convert between acceleration units including m/s², ft/s², g-force, and more. Essential for physics, automotive testing, and aerospace applications
Convert between angular acceleration units including rad/s², deg/s², and more. Essential for mechanical engineering and rotational dynamics
Convert between specific volume units including m³/kg, ft³/lb, and more. Essential for thermodynamics and fluid mechanics
Convert between moment of inertia units including kg·m², lb·ft², and more. Essential for mechanical engineering and rotational dynamics
Convert between moment of force units including N·m, lbf·ft, and more. Essential for mechanical engineering and statics
Convert between fuel efficiency units based on mass including g/kWh, lb/hp·hr, and more. Essential for automotive engineering and fuel analysis
Convert between fuel efficiency units based on volume including L/100km, mpg, and more. Essential for automotive engineering and fuel analysis
Convert between temperature interval units including K, °C, °F, and °R. Essential for thermodynamics and temperature difference calculations
Convert between thermal expansion coefficient units including 1/K, 1/°C, 1/°F, and more. Essential for materials science and engineering
Convert between thermal resistance units including K/W, °C/W, °F·hr/BTU, and more. Essential for heat transfer and insulation analysis
Convert between thermal conductivity units including W/m·K, BTU/hr·ft·°F, cal/s·cm·°C, and more. Essential for heat transfer analysis
Convert between specific heat capacity units including J/kg·K, BTU/lb·°F, cal/g·°C, and more. Essential for thermodynamics and heat calculations
Convert between heat density units including J/m³, BTU/ft³, cal/cm³, and more. Essential for heat storage and thermal analysis
Convert between heat flux density units including W/m², BTU/hr·ft², cal/s·cm², and more. Essential for heat transfer analysis
Convert between mass flow rate units including kg/s, lb/min, g/h, and more. Essential for chemical engineering and fluid dynamics
Convert between molar flow rate units including mol/s, kmol/h, lbmol/min, and more. Essential for chemical engineering and reaction kinetics
Convert between mass flux density units including kg/m²·s, lb/ft²·hr, g/cm²·min, and more. Essential for mass transfer analysis
Convert between molar concentration units including mol/L, mol/m³, lbmol/ft³, and more. Essential for chemistry and chemical engineering
Convert between solution concentration units including %, ppm, ppb, mg/L, and more. Essential for chemistry and environmental analysis
Convert between dynamic viscosity units including Pa·s, poise, centipoise, and more. Essential for fluid dynamics and rheology
Convert between kinematic viscosity units including m²/s, stokes, centistokes, and more. Essential for fluid dynamics and flow analysis
Convert between surface tension units including N/m, dyn/cm, lb/ft, and more. Essential for fluid mechanics and interfacial phenomena
Convert between permeability units including m², darcy, millidarcy, and more. Essential for petroleum engineering and porous media flow
Convert between luminance units including cd/m², nit, stilb, lambert, and more. Essential for lighting design and photometry
Convert between luminous intensity units including candela, lumen/steradian, and more. Essential for lighting design and photometry
Convert between illumination units including lux, foot-candle, phot, and more. Essential for lighting design and photometry
Convert between digital image resolution units including DPI, PPI, pixels/cm, and more. Essential for digital imaging and printing
Convert between frequency and wavelength units including Hz, THz, nm, μm, and more. Essential for optics and electromagnetic wave analysis
Convert between electric charge units including coulombs, ampere-hours, faradays, and more. Essential for electrical engineering and electrochemistry
Convert between linear charge density units including C/m, C/cm, and more. Essential for electrical engineering and electrostatics
Convert between surface charge density units including C/m², C/cm², and more. Essential for electrical engineering and electrostatics
Convert between volume charge density units including C/m³, C/cm³, and more. Essential for electrical engineering and electrostatics
Convert between electric current units including amperes, milliamperes, microamperes, and more. Essential for electrical engineering
Convert between linear current density units including A/m, A/cm, and more. Essential for electrical engineering and electromagnetics
Convert between surface current density units including A/m², A/cm², and more. Essential for electrical engineering and electromagnetics
Convert between electric field strength units including V/m, V/cm, kV/m, and more. Essential for electrical engineering and electrostatics
Convert between electric potential units including volts, millivolts, kilovolts, and more. Essential for electrical engineering
Convert between electric resistance units including ohms, milliohms, kilohms, and more. Essential for electrical engineering
Convert between electric resistivity units including Ω·m, Ω·cm, μΩ·cm, and more. Essential for electrical engineering and materials science
Convert between electric conductance units including siemens, millisiemens, and more. Essential for electrical engineering
Convert between electric conductivity units including S/m, S/cm, mS/cm, and more. Essential for electrical engineering and materials science
Convert between capacitance units including farads, microfarads, picofarads, and more. Essential for electrical engineering
Convert between inductance units including henries, millihenries, microhenries, and more. Essential for electrical engineering
Convert between magnetomotive force units including ampere-turns, gilberts, and more. Essential for electrical engineering and electromagnetics
Convert between magnetic field strength units including A/m, Oe, and more. Essential for electrical engineering and electromagnetics
Convert between magnetic flux units including webers, maxwells, and more. Essential for electrical engineering and electromagnetics
Convert between magnetic flux density units including teslas, gauss, and more. Essential for electrical engineering and electromagnetics
Convert between radiation activity units including becquerels, curies, and more. Essential for nuclear physics and medical imaging
Convert between radiation exposure units including roentgens, C/kg, and more. Essential for health physics and radiation protection
Convert between radiation absorbed dose units including grays, rads, and more. Essential for health physics and medical physics
Convert between SI prefixes including kilo, mega, giga, milli, micro, nano, and more. Essential for scientific notation and unit scaling
Convert between data transfer rate units including bits/s, bytes/s, Mbps, Gbps, and more. Essential for networking and data communication
Convert between sound units including decibels, bel, neper, and more. Essential for audio engineering and acoustics
Convert between typography units including points, picas, ems, rems, and more. Essential for graphic design and web development
Calculate percentages, percentage increase/decrease, find percentage of a number, and solve percentage problems with step-by-step solutions
Add, subtract, multiply, divide fractions, convert to decimals, and simplify fractions with step-by-step solutions
Calculate mean, median, mode, range, standard deviation, and variance with step-by-step calculations and data visualization
Convert between lumber volume units including board feet, cubic meters, cubic feet, and more. Essential for woodworking and construction
Add, subtract, multiply, and divide in binary, octal, decimal, or hexadecimal
Calculate convolution of two functions or sequences with step-by-step solutions
Calculate exponential growth and decay with initial value, growth rate, and time period
Calculate powers with negative and fractional exponents plus expanded form guidance
Calculate factorial values (n!) with exact results, digit counts, and reusable history
Find the greatest common factor (GCF) or greatest common divisor (GCD) of two or more numbers
Find the least common multiple (LCM) of two or more numbers
Calculate log, ln, custom base logarithm, and antilog in one free calculator
Calculate percent error between experimental and theoretical values
Solve quadratic equations using factoring, completing the square, and quadratic formula
Calculate ratios, simplify ratios, and find equivalent ratios
Basic calculator for addition, subtraction, multiplication, and division operations
Calculate SIP returns, plan investments, and achieve financial goals. Calculate step-up SIP, inflation-adjusted returns, and get detailed projections.
Calculate standard deviation, variance, and other statistical measures from a dataset
Calculate weighted averages where different values have different importance or weights
Calculate variance, standard deviation, and other statistical measures from a dataset
Solve constant-acceleration motion: displacement, velocity, acceleration, and time (SUVAT-style equations) for straight-line kinematics
Compute range, time of flight, max height, and impact velocity for projectile motion with configurable launch angle and gravity
Calculate net force, mass, or acceleration using Newton's second law and related linear dynamics relations
Compute kinetic and gravitational potential energy, work done, and simple work–energy relationships
Linear momentum, impulse, and one-dimensional elastic or inelastic collision estimates for introductory physics
Centripetal acceleration, force, angular speed, period, and radius for uniform circular motion
Density from mass and volume, buoyant force and apparent weight using Archimedes' principle for fluids
Period and frequency for a mass–spring system and simple pendulum; angular frequency ω from k, m, or length g
Solve V = IR, electric power P = IV, and equivalent resistance for resistors in series and parallel
Equivalent capacitance for capacitors in series and parallel; energy stored in a capacitor U = ½CV²
Resonant frequency, angular frequency, and period for an ideal LC tank circuit from inductance and capacitance
Torque from force and lever arm τ = rF sin θ; moment balance hints for simple rigid-body problems
Gravitational force between two masses and related scalars using Newton's law of universal gravitation
Object and image distances, focal length, and linear magnification for thin lenses and mirrors (sign conventions)
Refraction angles from indices of refraction; critical angle for total internal reflection at an interface
Observed frequency for moving source or observer (sound); optional EM-style recession formulas where applicable
Lorentz factor γ, time dilation, length contraction, and relativistic momentum or energy at high speeds
Angular momentum L = Iω, torque and angular acceleration for rigid bodies, rolling without slipping helpers
Ideal heat-engine efficiency η = 1 − Tc/Th and related thermodynamics estimates for Carnot cycles
Build ChatGPT custom instructions with presets for students, professionals, and creators. Copy each field or download. Runs in the browser.
Advanced scientific calculator with trigonometric and inverse trigonometric functions, logarithms, exponentials, and complex mathematical operations
Calculate the remainder when dividing two numbers (modulo operation)
Calculate the length of sides in right triangles using the Pythagorean theorem
Calculate sides, angles, area, and perimeter of right triangles
Perform arithmetic operations on complex numbers including addition, subtraction, multiplication, and division
Calculate nth roots including square root, cube root, and higher order roots
Convert numbers to and from scientific notation with arithmetic operations
Education has the broadest toolset on the site — 152 tools — because classroom and study needs span nearly every category: time management, everyday utilities, and the full range of math and science converters and calculators.
Teachers lean on the Pomodoro Timer and Countdown Timer for structuring class activities and timed tests, the Calendar for planning lesson schedules and due dates, and the Stopwatch for lab exercises and timed drills. The Notepad and Grocery List (handy for home-ec or event-planning units) cover quick note-taking and list-based classroom tasks, while the Appointment Scheduler and Medication Reminder show up in health-education and school-nurse contexts.
Where the catalog gets deep is math and science: nearly every physics, chemistry, and general unit converter on the site doubles as a study aid — students verifying homework answers, checking unit conversions for a lab report, or working through problem sets that mix metric and imperial units. Calculators covering percentages, geometry, and physics concepts help with everything from algebra homework to AP-level science coursework, and the formatting and encoding tools (JSON, Base64, text case) are increasingly used in intro computer-science classes.
Because the tools require no sign-up and run entirely in the browser, they work in school computer labs and on personal devices alike — a practical fit for classrooms where installing software isn't an option. This is less a curated toolkit than the site's general catalog viewed through an education lens, which is why it's by far the largest of the industry pages.