Online Calculators
Professional calculators for finance, health, engineering, and business.
Financial
(87 tools)Everyday Finance
Loan Calculator
Calculate monthly payments, total interest, and amortization schedules.
Mortgage Calculator
Calculate monthly mortgage payments with taxes and insurance, plus a full amortization schedule and extra payment payoff calculator.
Compound Interest Calculator
See how your investments grow with compound interest.
Savings Calculator
Project your savings over time with regular contributions.
Percentage Calculator
Calculate percentages, percentage change, and percent of a number.
VAT Calculator
Add or remove VAT from any amount.
Salary Calculator
Convert salary between hourly, weekly, monthly, and annual rates.
Interest Calculator
Calculate simple or compound interest, compare compounding frequencies, and see year-by-year growth.
Budget Calculator
Build a monthly budget across needs, wants, and savings, and compare against the 50/30/20 rule.
Tip Calculator
Calculate the tip, total bill, and per-person split for any service — with quick percentages and a round-up option.
Net Worth Calculator
Add up what you own and subtract what you owe — your net worth, debt-to-asset ratio, and financial health at a glance.
Emergency Fund Calculator
Find your emergency fund target from essential expenses, track progress, and see how long until you are fully funded.
Investing & Markets
TVM Calculator
Solve for present value, future value, rate, or periods using Time Value of Money.
NPV Calculator
Determine investment profitability by discounting future cash flows to the present.
IRR Calculator
Calculate the Internal Rate of Return — the expected annual growth rate of an investment.
CAGR Calculator
Compute the Compound Annual Growth Rate of any investment over a specified period.
Bond Yield Calculator
Find yield to maturity or fair price for any bond given coupon rate and term.
Dividend Yield Calculator
Calculate dividend yield, annual income from your shares, and yield on cost from price and per-payment dividends.
Corporate Finance
WACC Calculator
Calculate Weighted Average Cost of Capital from equity, debt, and preferred stock.
Operating Leverage Calculator
Analyze how a sales change impacts operating income using degree of operating leverage.
Business Valuation Calculator
Estimate enterprise value using EBITDA, revenue multiples, or P/E ratio.
Ad Revenue Calculator
Estimate daily, monthly, and annual ad revenue from page views, RPM, and fill rate.
DCF Calculator
Value an investment by discounting projected free cash flows and terminal value.
Asset Impairment Testing Calculator
Run an IAS 36 impairment test — compare carrying amount against recoverable amount (fair value less costs of disposal vs value in use).
Loan Loss Provision & Credit Risk Calculator
Calculate expected credit loss (ECL = EAD × PD × LGD) for a single exposure or an IFRS 9 staged portfolio.
Tax & Accounting
Depreciation Calculator
Calculate asset depreciation using Straight-Line, Double Declining, or Sum-of-Years.
Tax Bracket Calculator
Find your marginal tax rate and federal income tax liability by filing status (US 2024).
Payroll Calculator
Calculate gross-to-net pay with federal withholding, FICA, and state taxes (US).
Sales Tax Calculator
Add or remove sales tax from any amount for US states and international jurisdictions.
Income Tax Calculator
Estimate income tax liability across multiple countries with progressive bracket calculation.
Corporation Tax Calculator
Calculate corporate tax liability for UK, US, Ireland, Germany, and more.
PAYE Calculator
UK PAYE 2024/25 — calculate income tax, NI, pension, and take-home pay.
Withholding Tax Calculator
Calculate tax withheld at source on dividends, interest, royalties, and services.
Rental Income Tax Calculator
Calculate tax on rental income after allowable expenses and depreciation.
Property Tax Calculator
Estimate annual property tax from assessed home value, local mill/tax rate, assessment ratio, and homestead exemptions.
Capital Gains Tax Calculator
Estimate CGT on asset sales for US, UK, Australia, and more.
Betting Tax Calculator
Calculate tax on gambling winnings by jurisdiction. Includes US, UK, Australia, and more.
Turnover Tax Calculator
Simplified turnover-based tax for SMBs (South Africa, Philippines, Rwanda, and custom).
Cryptocurrency Tax Calculator
Calculate crypto capital gains tax using FIFO, LIFO, HIFO, or Average Cost. Covers US, UK, Australia, Canada and more.
Loans & Credit
Auto Loan Calculator
Calculate car loan payments including sales tax, trade-in, and full amortization.
Loan Amortization Calculator
Generate a full amortization schedule with optional extra payments to pay off early.
Lease vs Buy Calculator
Compare total cost of leasing versus buying a vehicle or asset over the full term.
Credit Card Payoff Calculator
Find how long to pay off your balance and how much interest you will pay.
Boat Loan Calculator
Calculate monthly boat loan payments including sales tax, trade-in, fees, and full amortization.
Down Payment Calculator
Calculate the down payment needed for a home, car, or major purchase, and the resulting loan amount.
Balloon Payment Loan Calculator
Calculate the monthly payment and final balloon payment on a balloon loan, plus total interest and total cost.
Debt Payoff Calculator
Compare snowball vs avalanche strategies across all your debts — time to debt-free and total interest for each.
Student Loan Calculator
Calculate student loan monthly payments and total interest, and see how extra payments shorten your payoff.
Debt Consolidation Calculator
Compare keeping your current debts against a consolidation loan — monthly payment, total interest, and break-even at a glance.
Repayment Calculator
Find the monthly payment for any debt, or how long repayment takes at your current payment — with total interest.
Business Loan Calculator
Calculate business loan payments with origination fees — actual cash received, total cost, and effective APR.
Lease Calculator
Calculate monthly lease payments from price, residual value, term, and rate — with depreciation and finance breakdown.
Shipping & Commerce
Shipping Rates Calculator
Estimate shipping costs by package weight, dimensions (dimensional weight), and carrier.
Car Rent Cost Calculator
Calculate total car rental cost including daily rate, insurance, extras, mileage, and fuel.
Commission Calculator
Calculate sales commission using flat rate, tiered brackets, or split between multiple reps.
Insurance & Protection
Savings & Retirement
Retirement Savings Calculator
Project your retirement nest egg and estimate monthly income based on savings, contributions, and returns.
Annuity Calculator
Calculate the future value of an annuity from principal, regular contributions, rate, and term — with year-by-year growth and scenario comparison.
Annuity Payout Calculator
Find how much an annuity pays out per period, or how long your savings will last at a given withdrawal rate.
Refinance Calculator
Calculate monthly savings, break-even point, and lifetime savings from refinancing a loan or mortgage.
401(k) Retirement Calculator
Project your 401(k) balance at retirement with employer match, salary growth, and returns — plus a 4% rule income estimate.
CD Calculator
Calculate certificate of deposit growth to maturity with any compounding frequency — interest earned and effective APY.
Utilities & Bills
Economics
GDP Calculator
Calculate Gross Domestic Product using the Expenditure Method (C + I + G + net exports).
Inflation Calculator
CPI inflation by year (1913–2024) plus forward and backward flat-rate modes — with a value chart.
GDP Per Capita Calculator
Measure economic output per person and compare living standards across countries.
Ratio Analysis
Gross Profit Ratio Calculator
Calculate gross profit ratio (gross margin) from net sales and cost of goods sold, with industry benchmarks.
Operating Ratio Calculator
Calculate the operating ratio — COGS plus operating expenses as a percentage of net sales — to measure operating efficiency.
Quick Ratio (Acid-Test) Calculator
Calculate the quick ratio (acid-test ratio) to measure short-term liquidity without relying on inventory.
Expense Ratio Calculator
Calculate the operating expense ratio — total expenses as a percentage of net sales — with a full cost breakdown.
Operating Profit Ratio Calculator
Calculate the operating profit ratio (operating margin) — operating profit as a percentage of net sales.
Net Profit Ratio Calculator
Calculate the net profit ratio (net margin) with a full income-statement walk from sales down to net profit.
Administrative Expenses Ratio Calculator
Calculate the administrative expenses ratio — admin overhead as a percentage of net sales — to benchmark back-office efficiency.
Debt Service Coverage Ratio (DSCR) Calculator
Calculate the Debt Service Coverage Ratio (DSCR) from net operating income and total debt payments to see if cash flow covers debt obligations.
Inventory Turnover Ratio Calculator
Calculate inventory turnover ratio and days inventory outstanding from COGS and average inventory, with industry benchmarks.
Receivables Turnover Ratio & Average Collection Period Calculator
Calculate accounts receivable turnover and average collection period (days sales outstanding) to measure how fast customers pay.
Payables Turnover Ratio & Average Payment Period Calculator
Calculate accounts payable turnover and average payment period to see how quickly a business pays its suppliers.
Working Capital Turnover Ratio Calculator
Calculate working capital turnover ratio to measure how efficiently a business uses working capital to generate sales.
Fixed Asset Turnover Ratio Calculator
Calculate the fixed asset turnover ratio to measure how efficiently a business uses fixed assets (PP&E) to generate sales.
Absolute Liquid Ratio Calculator
Calculate the absolute liquid ratio (cash ratio) — cash, bank, and marketable securities against current liabilities — the strictest test of short-term liquidity.
Earnings Yield Ratio Calculator
Calculate the earnings yield ratio (EPS ÷ share price) — the inverse of the P/E ratio — to compare stock earnings power against bonds and other assets.
Price Earning (P/E) Ratio Calculator
Calculate the price-to-earnings (P/E) ratio from share price and earnings per share to gauge stock valuation versus peers and the market.
Capital Gearing Ratio Calculator
Calculate the capital gearing ratio — fixed-cost capital (debt + preference shares) against equity shareholders' funds — to assess financial risk and leverage.
Proprietary Ratio Calculator
Calculate the proprietary ratio — shareholders' funds as a share of total assets — to see how much of the business is financed by owners versus creditors.
Debt-to-Equity Ratio Calculator
Calculate the debt-to-equity (D/E) ratio — total debt against shareholders' equity — to measure financial leverage and balance-sheet risk.
Health & Fitness
(35 tools)Core Health Metrics
BMI Calculator
Calculate your Body Mass Index (BMI) and health category.
BMR Calculator
Calculate your Basal Metabolic Rate and daily calorie needs.
Age Calculator
Calculate exact age in years, months, and days.
Calorie Calculator
Calculate daily calorie needs based on activity level — results in calories (kcal) or kilojoules (kJ).
Ideal Weight Calculator
Find your ideal body weight using multiple formulas.
Water Intake Calculator
Calculate daily water intake recommendations by gender, weight, and activity level.
Daily Life & Wellness
Sleep Quality Calculator
Find the best bedtime or wake-up time based on 90-min sleep cycles.
Pregnancy Due Date Calculator
Calculate your estimated due date, trimester, and milestones.
Period Calculator
Predict your next 6 periods, fertile windows, and ovulation dates.
Ovulation Tracker
Estimate your fertile window and ovulation day for family planning.
Blood Alcohol (BAC) Calculator
Estimate blood alcohol concentration by weight, gender, and drinks.
Step to Distance Calculator
Convert daily steps into km or miles based on your stride length — with walking time and calorie estimates.
Smoke Cost Calculator
Calculate how much smoking costs you daily, monthly, and yearly — and what you could save by quitting.
Dog & Cat Age Calculator
Convert your dog or cat's age into human years using modern veterinary guidance — with size adjustment and life stage.
Cardio & Workout
Target Heart Rate Calculator
Find your heart rate zones for fat burn, cardio, and peak training.
Calories Burned Calculator
Estimate calories burned for any exercise using MET values — results in calories (kcal) or kilojoules (kJ).
Pace Calculator
Calculate running pace, finish time, or distance with race projections.
VO2 Max Calculator
Estimate your cardiovascular fitness and VO2 max score.
Heart Rate Recovery Calculator
Measure how fast your heart recovers after exercise.
Wilks Calculator
Compare powerlifting strength across bodyweights using Wilks score.
Rest Timer Calculator
Find optimal rest periods between sets with a built-in timer.
One Rep Max (1RM) Calculator
Estimate your one-rep max from any set using Epley, Brzycki, Lombardi, and O'Conner formulas — with training percentages.
Nutrition & Calories
TDEE Calculator
Calculate your Total Daily Energy Expenditure by activity level.
Calorie Deficit / Surplus Calculator
Find your daily calorie target to lose, maintain, or gain weight.
Macro Calculator
Calculate ideal protein, carbs, and fat intake for your goal.
Nutrition Calculator
Calculate your personalised daily nutritional requirements — calories, protein, carbs, fat, fibre, and water.
Protein Calculator
Calculate your daily protein needs by weight, goal, and activity level — with per-meal targets and scenario comparison.
Fat Intake Calculator
Calculate your recommended daily fat intake (20–35% of calories) and saturated fat limit, based on your calorie needs.
Carbohydrate Calculator
Calculate daily carbohydrate needs for standard, low-carb, or keto eating styles, plus sugar limits and fibre targets.
Body Composition
Body Fat Percentage Calculator
Estimate body fat % using the US Navy circumference method.
Lean Body Mass Calculator
Calculate lean mass and fat mass using three established formulas.
Waist-to-Hip Ratio Calculator
Assess your body shape and cardiovascular risk with WHR.
Army Body Fat Calculator
Estimate body fat with the US Army tape test (AR 600-9) and check it against official age-group standards.
Engineering
(10 tools)Ohm's Law Calculator
Calculate voltage, current, resistance, and power.
Concrete Calculator
Calculate concrete volume for slabs, footings, and columns.
Pipe Volume Calculator
Calculate the volume and flow rate of a pipe.
Impulse Calculator
Calculate impulse (J = F·Δt = m·Δv) from force and time or from mass and velocity change — with average force.
Resistor Color Code Calculator
Free resistor color code calculator — decode 3, 4, 5, and 6-band resistors to resistance, tolerance, and temp coefficient with a live preview.
LED Resistor Calculator
Free LED resistor calculator — exact and standard (E24) resistor values for any LED circuit, with power rating and live circuit diagram.
Voltage Divider Calculator
Free voltage divider calculator — output voltage, current, and power dissipation from Vin, R1, and R2.
Velocity & Acceleration Calculator
Free kinematics calculator — solve final velocity, acceleration, or displacement with the constant-acceleration equations.
Torque Calculator
Free torque calculator — τ = F × r × sin(θ) in N·m, lb·ft, lb·in, and kg·cm, with angle efficiency shown.
Density Calculator
Free density calculator — solve density, mass, or volume from the other two, with unit conversions and a float-or-sink check.
Business
(6 tools)ROI Calculator
Calculate Return on Investment (ROI) percentage.
Profit Margin Calculator
Calculate gross, operating, and net profit margins — plus stock trading margin and currency exchange margin modes.
Break-Even Calculator
Find the break-even point for your business or product.
Payback Period Calculator
Calculate simple and discounted payback periods for any investment — with cash flow growth and time-value warnings.
Discount Calculator
Calculate sale price after discount or find discount percentage.
Markup Calculator
Calculate selling price from cost with desired markup.
Math & Education
(39 tools)Arithmetic & Algebra
Operation Calculator
Perform quick calculations — add, subtract, multiply, and divide — with all four results at a glance and history.
Factor Calculator
Find all factors, prime factorization, GCF, and LCM of any whole number.
Root Calculator
Calculate square roots, cube roots, nth roots, and simplify radical expressions.
Factorial Calculator
Calculate factorials (n!) instantly with a step-by-step product chain and quick reference table.
Exponent Calculator
Calculate powers, negative and fractional exponents, and scientific notation with full step-by-step breakdowns.
Rounding Calculator
Round any number to the nearest whole, tenth, hundredth, ten, hundred, and more — with half-up, banker's rounding, ceiling, floor, and truncate modes.
Percent Error Calculator
Calculate percent error between a measured/estimated value and the actual value, with absolute and signed error.
GPA Calculator
Calculate your semester and cumulative GPA (Grade Point Average) on the 4.0 scale from course grades and credits.
Fractions Operations Calculator
Add, subtract, multiply, and divide fractions — with simplified results, mixed numbers, decimals, and step-by-step working.
Statistics Calculator
Free statistics calculator — mean, median, mode, range, variance, and standard deviation (sample and population) from any list of numbers.
Quadratic Equation Solver
Free quadratic equation solver — real and complex roots, discriminant, and vertex of ax² + bx + c = 0, with the formula shown.
Permutations & Combinations Calculator
Free nPr and nCr calculator — exact permutation and combination counts with formulas, for probability and counting problems.
Log Calculator
Free logarithm calculator — log to any base, plus natural log (ln), log₁₀, and log₂, with verification and change-of-base.
Numbers & Conversions
Binary ⇄ Decimal Converter
Convert between binary, octal, decimal, and hexadecimal with a place-value breakdown.
Hex to RGB Converter
Convert hex color codes to RGB/HSL, preview the swatch, and check text contrast.
Fraction to Decimal Converter
Convert fractions to decimals and decimals back to simplified fractions, step by step.
Decimal to Percent Converter
Convert decimals to percentages and percentages back to decimals with clear rules.
Minutes to Decimal Converter
Convert minutes and hours into decimal hours for payroll, billing, and timesheets.
Roman Numerals Converter
Convert numbers to Roman numerals and back, with a symbol-by-symbol breakdown.
Numbers to Words Converter
Convert any number into English words — plain, currency, or check-writing format — up to the quadrillions.
Geometry & Shapes
Geometry Calculator
Calculate area, perimeter, volume, and surface area for common 2D and 3D shapes.
Rhombus Calculator
Calculate the area, perimeter, diagonals, height, and angles of a rhombus from diagonals, side and angle, or side and height.
Stadium Calculator
Calculate the area and perimeter of a stadium shape (discorectangle) — a rectangle capped by two semicircles.
Hemisphere Calculator
Calculate the volume, curved surface, base area, and total surface area of a hemisphere from its radius.
Pyramid Calculator
Calculate the volume, surface area, slant heights, and lateral edges of a square or rectangular pyramid.
Prism Calculator
Calculate the volume, surface area, and diagonal of a rectangular prism (box) — or any prism from base area and length.
Triangular Prism Calculator
Calculate the volume and surface area of a triangular prism from the three triangle sides (Heron's formula) or base and height.
Rectangular Prism Calculator
Calculate the volume, surface area, and space diagonal of a rectangular prism (box) from length, width, and height.
Hypotenuse Calculator
Find the hypotenuse of a right triangle from its two legs using the Pythagorean theorem.
Right Triangle Side and Angle Calculator
Solve any right triangle for missing sides and angles from any two known values.
Radius of a Circle Calculator
Calculate the radius of a circle from its diameter, circumference, or area — with reverse calculations too.
Tube Volume Calculator
Calculate the material volume, inner capacity, and surface area of a tube (hollow cylinder) from its radii and length.
Ellipsoid Volume Calculator
Calculate the volume and approximate surface area of an ellipsoid from its three semi-axes a, b, and c.
Conical Frustum Surface Area Calculator
Calculate the total and lateral surface area, slant height, and volume of a conical frustum from its radii and height.
Slope & Distance Calculator
Free slope calculator — slope, distance, midpoint, angle, and line equation between any two points on a graph.