Calculators

Calculate percentages, tip amounts, and percentage changes with precision

Advanced multi-functional calculator with trigonometric, logarithmic, and exponential functions

Calculate mean, median, mode, standard deviation, and variance for sets of data

Add, subtract, multiply, and divide fractions, and simplify them to lowest terms

Calculate your exact age in years, months, weeks, days, and even minutes

Convert your dog or cat's age to human years based on species, size, and AVMA guidelines

Track your academic performance with weighted GPA and semester grade estimates

Compute network ranges, broadcast addresses, and CIDR masks for IPv4 networking

Compute your ideal body weight based on multiple scientific formulas

Calculate monthly EMI, total payment, and interest for loans

Calculate your monthly car payment with sales tax, trade-in, down payment, and fees

Solve for any side of a right triangle using a² + b² = c² and see area, perimeter, and squared values

Compute mean, median, mode, range, sum, and standard deviation for any list of numbers

Calculate sample and population standard deviation, variance, mean, and sum for any dataset

Solve quadratic equations ax² + bx + c = 0 with real and complex roots, plus discriminant analysis

Compute permutations P(n, r), combinations C(n, r), and factorials for any n and r

Solve right triangles given any two sides or a side and an angle — find legs, hypotenuse, angles, area, and perimeter

Generate arithmetic, geometric, and Fibonacci-like sequences with nth term and sum calculations

Calculate concrete volume in cubic yards, meters, or feet for slabs, footings, columns, and tubes — plus pre-mix bag estimates

Calculate weekly work hours from clock-in/out times across multiple days, with break deductions, overtime, and gross pay estimates

Calculate area in square feet, meters, yards, or acres for rectangles, circles, triangles, and trapezoids — with cost estimation for flooring or paint

Calculate the perceived 'feels-like' temperature from air temperature and wind speed using the NWS wind chill formula, with frostbite risk levels

Calculate the perceived 'feels-like' temperature from air temperature and humidity using the NWS Rothfusz regression, with heat-stress risk levels

Convert mass between kilograms, pounds, ounces, grams, stones, tons, carats, grains, and more — instant multi-unit display

Convert volume between liters, gallons (US/UK), cups, fluid ounces, cubic meters, cubic feet, and more — supports cooking and engineering units

Convert speed between m/s, km/h, mph, ft/s, knots, Mach, and the speed of light — instant multi-unit results

Convert pressure between psi, bar, kPa, MPa, atm, mmHg, inHg, torr, mbar, and more — instant multi-unit display

Calculate the difference between two dates in days, weeks, months, and years

Convert between units of length, weight, temperature, area, and volume

Free tip calculator — instantly calculate how much to tip and split the bill between any number of people. Choose your tip percentage or enter a custom amount. Perfect for restaurants, delivery, and services.

Calculate discounted price, savings amount, and discount percentage

Convert time between different time zones around the world

Estimate your monthly mortgage payments, including taxes, insurance, and PMI

Calculate how your investments grow over time with compound interest and regular contributions

Calculate the purchasing power of money over time based on inflation rates

Add or remove VAT from any amount instantly with preset rates and multiple currency symbols

Convert amounts between 25+ world currencies using approximate exchange rates

Calculate return on investment, net profit, annualized ROI, and investment multiple

Convert numbers to Roman numerals and Roman numerals back to numbers — with step-by-step breakdown

Calculate the Nth Fibonacci number or list Fibonacci numbers with golden ratio approximation

Check if a number is prime, find its factors, or list all primes up to a given limit

Interactive periodic table of elements — search by name, symbol, or atomic number, with detailed info on each element

Calculate the molar mass (molecular weight) of any chemical formula — with element-by-element composition breakdown

Calculate pH, pOH, [H⁺], and [OH⁻] from any input — includes strong/weak acid and base modes, Henderson-Hasselbalch buffer, and Ka/Kb presets for common compounds

Solve any stoichiometry problem from a balanced equation — compute moles, mass, gas volume (ideal gas), and solution amounts for every reactant and product, with limiting reagent finder, percent yield, and mass-conservation verification

Automatically balance any chemical equation — enter reactants and products, get the balanced stoichiometry with element-by-element audit

Calculate voltage, current, resistance, and power — enter any 2 values to solve for the rest, with auto unit scaling

Decode resistor color bands (3, 4, 5, 6-band) to resistance value — or enter a value to find the bands. Includes tolerance and temperature coefficient.

Decode capacitor codes (104, 4n7), compute series/parallel capacitance and inductance, find reactance, LC resonance, and RC/RL time constants

Calculate the correct resistor value for any LED circuit — single LED, series, or parallel configurations with E24 standard values, power budget, and circuit diagrams

Calculate voltage drop, wire resistance, and ampacity for any AWG wire gauge — copper or aluminum, with wire size recommendations per NEC

Calculate output voltage, find R1 or R2 for any voltage divider — includes load effects, E24 standard resistor matching, and circuit diagrams

Calculate 555 timer circuits — astable oscillator frequency, duty cycle, and monostable pulse width with component design, circuit diagrams, and waveform preview

Calculate projectile trajectory, range, max height, and flight time — with launch angle slider, trajectory visualization, and planetary gravity presets

Calculate orbital velocity, gravitational force, escape velocity, and Hohmann transfer orbits — with presets for Earth, Moon, Mars, Jupiter and more

Calculate the speed of sound in air, water, steel, and 20+ media — with Mach number converter, thunder distance estimator, altitude and humidity corrections

Estimate your retirement savings, monthly income, and inflation-adjusted totals

Calculate break-even point, contribution margin, and units needed to hit your profit target

Compare the true cost of renting vs buying a home over time, including mortgage, taxes, maintenance, and investment opportunity cost

Track your assets and liabilities to calculate your total net worth with an interactive balance sheet

Create professional invoices with line items, tax, discount, and multiple currencies — print or save as PDF

Calculate take-home pay, federal tax, FICA, and 401(k) contributions based on US 2024 tax brackets

Calculate your exact take-home pay per paycheck with federal & state taxes, FICA, 401(k), HSA, and health insurance deductions

Generate random numbers, pick from ranges, roll dice, and create random sequences with cryptographic randomness

Convert file sizes between bytes, KB, MB, GB, TB, bits and binary units (KiB, MiB, GiB) — instant and accurate

Boost productivity with a customizable Pomodoro timer — set work and break intervals, track sessions, and stay focused

Calculate and convert aspect ratios for images, videos, and screens — find missing dimensions instantly

Calculate fuel cost for any trip — enter distance, fuel efficiency, and price per liter or gallon

Calculate the electricity cost of any appliance — enter wattage, hours of use, and your electricity rate

Generate a full month-by-month amortization table showing principal, interest, and remaining balance

Calculate how long to reach your savings goal — or how much to save monthly to hit it by a target date

Count working days between two dates or add/subtract business days — excludes weekends and US federal holidays, supports custom holidays

Calculate running pace, finish time, or distance — supports km/mi, race presets for 5K, 10K, half and full marathon

Add or subtract days, weeks, months, or years to any date — find what date is 90 days from today or 6 months ago

Xem âm lịch, can chi, ngũ hành, giờ hoàng đạo và 24 tiết khí cho bất kỳ ngày nào — đổi dương lịch sang âm lịch chính xác theo múi giờ Việt Nam

Find the best meeting time across multiple time zones — add cities and see overlapping work hours at a glance

See the current time in multiple cities simultaneously — add any timezone, drag to reorder, toggle 12h/24h

See exactly which tax bracket each dollar of your income falls into with a visual marginal rate breakdown

Calculate how many months of expenses you have saved and how much more you need to reach your goal

Add or subtract durations (days, hours, minutes, seconds), find the time between two dates, or shift a date by any duration

Solve any triangle from SSS, SAS, ASA, AAS, or SSA — find sides, angles, area, perimeter, heights, inradius, and circumradius

Solve a loan two ways — fixed term to monthly payment, or fixed payment to payoff time, with total interest and total paid

Solve for the unknown interest rate from present value, payment, term, and future value — finds nominal and effective annual rates

See how an investment grows over time with simple vs compound interest, optional monthly contributions, and a yearly balance schedule

Solve for end balance, starting amount, monthly contribution, return rate, or years — flexible 5-variable investment planner

Time Value of Money solver — compute any one of PV, FV, PMT, N, or I/Y given the other four. Like an HP-12C in your browser

Estimate US federal income tax for 2024/2025 with filing status, standard or itemized deductions, and FICA — see effective vs marginal rate

Compute b raised to the n — supports negative, fractional, and very large exponents with scientific-notation output

Calculate log base b of x — auto-shows ln, log₁₀, and log₂ side by side using the change-of-base formula

Find the greatest common factor and least common multiple of any list of integers — with prime factorization breakdown

Solve a:b = c:d for any missing value, simplify ratios, and check proportional relationships

Calculate the slope of a line through two points, get y-intercept, line equation, angle, and distance — handles vertical lines

Compute Euclidean distance and midpoint between two points in 2D or 3D coordinate space

Calculate the volume and surface area of cubes, boxes, spheres, cylinders, cones, pyramids, and capsules

Compute union, intersection, conditional, and complementary probabilities — plus binomial P(X=k), P(X≤k), and P(X≥k)

Convert a raw score to a z-score with normal-distribution probabilities for left, right, and two-tailed tests

Compute one- and two-tailed p-values from a Z or Student's t statistic, with significance verdict at α = 0.05, 0.01, 0.001

Compute confidence intervals for a sample mean or proportion at any confidence level — uses normal approximation

Project your 401(k) balance at retirement with employee contributions, employer match cap, salary growth, and investment returns

Calculate the down payment needed for any home price, or how long to save it given your monthly contributions and return rate

Find how much house you can afford using DTI and housing-ratio caps, accounting for taxes, insurance, HOA, and existing debts

Compare your current mortgage with a refinance offer — see monthly savings, break-even months on closing costs, and lifetime savings

Compute the true Annual Percentage Rate of a loan including points, origination, and closing costs — different from the stated rate

Convert between nominal annual rate and effective APY (Annual Percentage Yield) for any compounding frequency, plus continuous compounding

Project the final balance and interest of a Certificate of Deposit, with optional after-tax estimate and yearly balance schedule

Project your Roth IRA balance at retirement and compare after-tax outcomes vs a Traditional IRA at your future tax bracket

Calculate monthly vehicle lease payments using money factor, residual value, sales tax, down payment, and trade-in

See how an extra monthly payment shortens your mortgage and saves interest — payoff months, dollars saved, and new total

Add, subtract, multiply, scale, transpose, find the determinant or inverse of any matrix up to 4×4

Compute a mod n with quotient breakdown — supports BigInt for arbitrary-size integers and shows both math and truncating mod

Solve any of N₀, N(t), half-life, or elapsed time for first-order decay — useful for radioactive isotopes and drug clearance

Arbitrary-precision integer arithmetic — add, subtract, multiply, divide, modulo, exponent, and factorial with no float overflow

Calculate the volume of horizontal/vertical cylindrical, rectangular, spherical, capsule, and oval tanks in gallons or liters

Calculate how many tiles you need to cover a floor or wall, with adjustable waste percentage and total cost estimate