Master Directory

All Free Online Calculators A-Z

Comprehensive alphabetical directory of all 37+ precision online calculators across financial, algebraic, fractional, unit, and network categories.

💰 Financial Calculators

• Personal & Loan Calculator — Calculate monthly payments, total interest, and amortization schedule for any loan.
• Compound Interest Calculator — Calculate the future value of your savings and investments with daily, monthly, or annual compounding.
• Simple Interest Calculator (I = Prt) — Calculate simple interest, principal, rate, time, and total maturity amount with step-by-step formula.
• Mortgage Payment Calculator — Estimate monthly home mortgage payments including principal, interest, and term calculations.
• Auto & Car Loan Calculator — Calculate monthly car payments, total loan cost, and interest on vehicle purchases.
• Sales Tax & Discount Calculator — Calculate total retail price, state and local sales tax amount, and percentage discount savings.
• Tip Calculator & Bill Splitter — Calculate restaurant tips, gratuity percentages, and split bills evenly among multiple people.
• Salary & Hourly Wage Calculator — Convert hourly pay to salary, bi-weekly, monthly, and annual gross earnings with overtime.
• Credit Card Payoff Calculator — Calculate months to become debt-free, total interest charges, and debt payoff savings.
• Future Value (FV) Calculator — Calculate the future value of periodic savings, lump sums, annuities, and compound interest.
• Profit Margin & Markup Calculator — Calculate gross profit margin, markup percentage, cost of goods, and selling price.
• Asset Depreciation Calculator — Calculate asset depreciation schedules using Straight-Line, Double Declining Balance, and SYD.
• Live Gold Price, Carat Purity & Jewelry Value Calculator — Calculate live gold value by weight (grams, troy ounces, tola/vori, kg) across 24K, 22K, 18K, 14K purities with making charges, VAT, scrap value, and live interactive gold trend charts.
• Live Bitcoin Converter, Satoshi Matrix & DCA Profit Calculator — Convert BTC and Satoshis to USD, EUR, GBP, JPY, CAD, AUD, INR, and BDT with live spot prices, historical DCA backtesting, Bitcoin Halving countdown, and mining profitability.
• Retirement & 401(k) Savings Calculator — Calculate your retirement nest egg, monthly 401(k) / IRA contributions, safe withdrawal rate, and retirement timeline.
• ROI (Return on Investment) Calculator — Calculate total return on investment percentage (ROI %), annualized ROI (CAGR), and net profit from any venture.
• Present Value (PV) Calculator — Calculate the current worth of a future sum of money or stream of cash flows given a specified discount rate.
• Inflation & Purchasing Power Calculator — Calculate how inflation erodes purchasing power, future equivalent costs, and cumulative price increases over time.
• Debt-to-Income (DTI) Ratio Calculator — Calculate your front-end and back-end debt-to-income ratio, mortgage borrowing capacity, and lender qualification limits.
• CD (Certificate of Deposit) / Fixed Deposit (FDR) Calculator — Calculate CD interest earnings, maturity balance, compounding yield, and early withdrawal penalties for bank certificates of deposit.
• Early Loan Payoff & Extra Payment Calculator — Calculate total interest saved and payoff time eliminated by making extra monthly, annual, or lump-sum loan payments.
• APR to APY Converter & Interest Rate Calculator — Convert nominal Annual Percentage Rate (APR) to effective Annual Percentage Yield (APY) and vice versa with compounding frequencies.
• Rule of 72 Calculator — Calculate how long it takes for an investment to double at a given annual interest rate using the Rule of 72 mental math versus the exact logarithmic formula.
• Break-Even Point Calculator — Calculate your business break-even point in units and sales revenue based on fixed costs, variable costs, and selling price.
• SIP (Systematic Investment Plan) Calculator — Calculate the future value of monthly SIP investments with annual step-up, total invested amount, and estimated wealth gains.
• CAGR Calculator (Compound Annual Growth Rate) — Compute the compound annual growth rate from beginning and ending values with annualized return, total return, growth multiple, and a constant-rate growth path.
• Dividend Calculator (Yield, Shares & Income) — Calculate dividend yield, shares owned, annual and monthly dividend income, and income per $1,000 invested from stock price and dividend per share.
• Debt Snowball & Avalanche Calculator (Payoff Planner) — Build a debt payoff plan: snowball or avalanche order, months to debt-free, total interest, debt-free date, and savings versus minimum payments only.
• Home Affordability Calculator (28/36 Rule) — Estimate how much house you can afford from income, debts, down payment, rate, taxes, and insurance using lender front-end and back-end DTI caps.
• Amortization Schedule Calculator (Loan Payoff Table) — See every payment of a fixed-rate loan with a full amortization schedule: monthly principal, interest, remaining balance, extra-payment savings, and payoff date.
• Forex Position Size Calculator — Calculate the exact lot size for any trade from your account balance, risk percentage, and stop-loss distance — position sizing is the number one risk-management rule in forex.
• Pip Value Calculator — Convert pip movement into cash value for any currency pair and lot size — standard, mini, and micro lots with JPY-pair and cross-pair conversion support.
• Forex Gain & Loss Calculator — Turn entry price, exit price, and lot size into pip gain or loss and cash profit or loss for long and short trades, with return on notional.
• Pivot Point Calculator — Generate classic, Woodie, and Fibonacci pivot points with R1–R3 and S1–S3 support and resistance levels from the previous period's high, low, and close.
• Forex Market Hours & Session Converter — See which forex session is open right now in your local timezone — Sydney, Tokyo, London, and New York hours plus the high-volume overlap windows.
• Rent Affordability Calculator (30% Rule) — Maximum rent from your gross income under the 30% rule, the 28/36 debt ratios, and the 40x landlord income test — plus a reverse check of your current rent share.
• Stock Profit Calculator (Buy/Sell P/L & Fees) — Buy and sell price, share count, and round-trip commission math — net profit or loss, ROI percentage, per-share gain, and the break-even sell price including fees.
• Rent vs Buy Calculator (Breakeven & Opportunity Cost) — Compare renting against buying over your horizon: mortgage P&I, tax, insurance, maintenance, equity at sale, opportunity cost, and the exact year buying pulls ahead.
• VAT Calculator (Add or Extract VAT %) — Add VAT to a net price or extract VAT from a tax-inclusive gross price at any rate — net, tax, and gross amounts with common UK, EU, India and Bangladesh rates.
• Overtime Pay Calculator (1.5x, Double-Time & OBBBA Deduction) — Calculate overtime pay at time-and-a-half or double time, split OT wages into base and premium portions, and estimate the 2026 OBBBA overtime deduction — up to $12,500 single or $25,000 joint with the MAGI phase-out.
• Paycheck Calculator (Take-Home Pay After Taxes) — Estimate your 2026 U.S. take-home pay — federal income tax, Social Security, Medicare, pre-tax 401(k) and HSA deductions, plus optional state withholding — as net pay per paycheck with effective and marginal rates.
• Buy Now Pay Later Calculator (Pay in 4 & Installments) — Split any purchase into four interest-free biweekly payments or 6- and 12-month installment plans — payment dates, total cost, late-fee exposure, and a credit card payoff comparison.
• Holiday Budget Calculator (Christmas & Gift Spending Planner) — Plan the whole holiday season before shopping starts — gifts by group, food and hosting, decorations, travel, and cards — then see the monthly savings target to pay for it in cash instead of January's credit card bill.
• Wedding Budget Calculator (Cost Breakdown & Savings Plan) — Build a wedding budget from guest count and style — the $292 per-guest national average, category splits for venue, catering, photography, and flowers, plus the monthly savings plan to fund the day debt-free.
• YouTube Money Calculator (Ad Revenue & RPM Estimator) — Estimate monthly YouTube ad revenue from views and niche RPM ranges — the creator share after YouTube's 45% cut, revenue per video, and the views needed to reach a monthly income goal.
• Self-Employment Tax Calculator (1099 & Quarterly Taxes) — Estimate 2026 self-employment tax on freelance and 1099 income — 15.3% SE tax on 92.35% of net earnings, the half deduction, QBI, federal income tax, and the quarterly payment due each quarter.
• 2026 Federal Tax Bracket Calculator (Marginal vs Effective) — Find your 2026 U.S. federal income tax bracket and see how each slice of income is taxed across the seven progressive rates — marginal bracket, effective rate, and total federal tax for single, married, and head-of-household filers.
• Estate Tax Calculator (2026 $15M Exemption) — Estimate 2026 federal estate tax under the OBBBA $15,000,000 exemption — 40% on every dollar above the line, $30 million for married couples electing portability, and how much headroom your estate has left.
• Capital Gains Tax Calculator (2026 LTCG, STCG & NIIT) — Estimate the 2026 federal tax on an investment profit — long-term gains at 0/15/20%, short-term gains as ordinary income, plus the 3.8% Net Investment Income Tax — and see what you keep after tax.
• Social Security Calculator (2026 PIA, 62 vs 67 vs 70) — Estimate your monthly Social Security retirement benefit at any claim age from 62 to 70 using the 2026 AIME bend-point formula, compare every claiming age side by side, and find the cumulative break-even point.
• HELOC Calculator (Home Equity Line of Credit Payments) — Estimate your HELOC borrowing power — available equity at 80% combined LTV, the interest-only draw payment, the full repayment payment once principal kicks in, and the payment shock between them.
• Mortgage Refinance Calculator (Break-Even & Savings) — Compare your current mortgage against a refinance — new payment, monthly savings, closing-cost break-even point, and total interest saved over your planned time in the home, with a clear worth-it verdict.
• Student Loan Calculator (Payment & Extra-Payoff) — Estimate your student loan payment on the Standard 10-year plan, see total interest over the term, and find how much interest and time extra monthly payments save — with notes on IDR, SAVE, and PSLF.
• Car Affordability Calculator (20/4/10 Rule) — Find the maximum car price you can afford from your income — using the 20/4/10 guideline that keeps total transportation costs (payment, insurance, fuel, maintenance) at or below 20% of gross income — with max payment and financed amount.
• Tip Tax Calculator 2026 (OBBBA No Tax on Tips) — Estimate your 2026 OBBBA tip deduction — the $25,000 per-return cap, the 10% phase-out above $150,000 single or $300,000 joint MAGI, and the federal tax saved while FICA still applies to every tip dollar.
• Senior Deduction Calculator 2026 ($6,000 Per Person 65+) — Check the 2026 OBBBA senior deduction — $6,000 per person age 65 or older, reduced 6% per person by MAGI above $75,000 single or $150,000 joint, and fully gone at $175,000 or $250,000.
• IRS Mileage Rate Calculator 2026 (76¢ Mid-Year Rate) — Calculate your 2026 mileage tax deduction with the IRS mid-year rate change — 72.5¢ per mile for January–June and 76¢ for July–December — and compare the standard deduction against actual vehicle expenses.
• 401k Contribution Calculator 2026 (Limits, Catch-Up & Match) — Check your 2026 401(k) contribution limits — $24,500 employee deferral, $8,000 catch-up at 50+, $11,250 super catch-up at 60–63, and the $72,000 combined cap — with employer match math and pre-tax vs Roth savings.
• Tax Refund Calculator 2026 (Federal Refund or Amount Owed) — Estimate your 2026 federal tax refund — bracket-based liability after the standard deduction and child tax credit, minus what you withheld — as a refund or amount owed before you file.
• Child Tax Credit Calculator 2026 ($2,200 Per Child + ACTC) — Estimate your 2026 child tax credit — $2,200 per child under 17, up to $1,700 refundable through the Additional Child Tax Credit, and the $200,000 / $400,000 MAGI phase-out, with the refund it adds.

➗ Math & Statistics Calculators

• Standard Online Basic Calculator — Classic handheld online calculator with LCD display, memory keys (MC, MR, M+, M-), and history tape.
• Scientific Calculator with Step Breakdown — Evaluate expressions with trigonometry, logarithms, roots, powers, constants, parentheses, and factorial using a full scientific keyboard in degree or radian mode.
• Percentage Calculator (3-in-1) — Calculate what is X% of Y, percentage increase/decrease, and X is what percent of Y.
• Fraction Arithmetic Calculator (+, −, ×, ÷) — Add, subtract, multiply, and divide fractions with step-by-step common denominators and simplification.
• Fraction to Decimal Calculator — Convert proper and improper fractions or mixed numbers into terminating or repeating decimals.
• Decimal to Fraction Calculator — Convert any decimal number into a simplified proper fraction, improper fraction, or mixed number.
• Mixed Numbers Calculator (½) — Add, subtract, multiply, and divide mixed numbers with whole numbers and proper fractions.
• Fraction Simplifier & Reducer — Reduce fractions to their simplest lowest terms using the Greatest Common Divisor (GCD).
• GCF & LCM Calculator — Find the Greatest Common Factor (GCF) and Least Common Multiple (LCM) of multiple integers.
• Prime Factorization & Factor Tree Calculator — Find prime factors, exponential prime decomposition, all positive divisors, and factor count.
• Ratio & Proportion Calculator (A:B = C:D) — Solve proportions (A : B = C : D), simplify multi-term ratios, and divide amounts proportionally.
• Quadratic Formula Solver (ax² + bx + c = 0) — Solve quadratic equations with real and complex roots, discriminant analysis (Δ = b² - 4ac), and vertex.
• Mean, Median, Mode & Range Calculator — Find the average (mean), middle value (median), most frequent value (mode), and range for any data set.
• Standard Deviation & Variance Calculator — Calculate sample and population standard deviation (s, σ), variance (s², σ²), and sum of squares with deviation steps.
• Combination & Permutation Calculator (nCr / nPr) — Calculate combinations (nCr) and permutations (nPr) with factorials, step-by-step product expansion, and locks/arrangements explanations for probability problems.
• Scientific Notation Calculator & Converter — Convert standard numbers to scientific notation (a × 10ᵇ), engineering notation, and E-notation format.
• Exponent & Power Calculator (xʸ) — Calculate base raised to any power (xʸ), including negative, fractional, and zero exponents.
• Slope Calculator (Slope, Intercept, Equation & Distance) — Find the slope of a line through two points with rise over run, y-intercept, straight-line equation, angle of inclination, and point-to-point distance.
• Probability Calculator (Events, Odds & Dice Sums) — Calculate single-event probability, complement, odds, and 1-in-x chances, plus dice-sum probabilities with the full outcome distribution table.
• Pythagorean Theorem Calculator (Right Triangle Solver) — Find any missing side of a right triangle with the Pythagorean theorem, plus area, perimeter, and both acute angles with step-by-step substitutions.
• Random Number Generator (Range, Unique, Sorted) — Generate secure random numbers in any range with count, unique-draw, and sort options, plus generation history and the odds behind every draw.
• Weighted Grade Calculator (Final Exam Requirement) — Weighted course grade and letter grade from category percentages, plus the final exam score needed to reach any target class average.
• GPA Calculator (Cumulative & Weighted) — Letter grades and credits in, term GPA out — with cumulative GPA from prior terms, quality-point totals, and 4.0 / 4.3 / 5.0 scale switching.
• Discount Calculator (Percent Off + Coupon + Tax) — Stack two percent-off deals, a coupon, quantity, and sales tax to get the final price, the per-item price, and exactly how much you saved.
• Roman Numeral Converter (Numbers ↔ Roman Numerals) — Two-way converter for 1–3999 with a live digit-by-digit breakdown, canonical-form checking, and the subtractive rule demonstrated on every value.

🔄 Unit Conversion Calculators

• Temperature Unit Converter — Convert between Celsius (°C), Fahrenheit (°F), Kelvin (K), and Rankine (°R) scales.
• Length & Distance Converter — Translate meters, feet, inches, centimeters, kilometers, miles, and yards with exact conversion ratios.
• Weight & Mass Converter — Convert kilograms (kg), pounds (lbs), ounces (oz), grams (g), stone (st), and tons with exact ratios.
• Area & Volume Unit Converter — Convert square meters, square feet, acres, hectares, liters, gallons, cubic meters, and fluid ounces between metric and imperial systems.
• Speed & Velocity Unit Converter — Convert miles per hour, kilometers per hour, meters per second, feet per second, and knots for vehicles, aviation, running pace, and maritime speeds.
• Data Size & Digital Storage Converter — Convert digital storage units — bits, bytes, kilobytes, megabytes, gigabytes, and terabytes — using both decimal (SI) and binary (IEC) standards, with transfer-time estimates.
• Pressure Converter (Pa, Bar, ATM, PSI, Torr) — Convert pressure between pascal, kilopascal, bar, atmosphere, PSI, torr and mmHg with exact conversion factors and a full all-unit reference table.
• Gas Mileage Calculator (MPG & Trip Fuel Cost) — Calculate fuel economy in MPG and L/100km, gallons or liters needed, total trip fuel cost, and cost per mile from distance, MPG, and gas price.
• Concrete Calculator (Slabs, Columns & Bags) — Slab, round-column, and wall volumes with a waste margin, converted to cubic yards, cubic feet, and the exact bag count for 80 lb and 60 lb bags.
• Paint Calculator (Gallons & Cans per Room) — Wall area from room dimensions minus doors and windows, scaled by coats and coverage, then rounded into 1-gallon and 5-gallon cans with a cost estimate.
• Square Footage Calculator (Rooms & Floors) — Room area for rectangles, L-shapes, circles, and triangles with a running project total, perimeter, and flooring cost per square foot in one pass.
• Fuel Cost Calculator (Trip Gas Price) — Gallons needed, total fuel spend, cost per mile, and the per-passenger split for one-way or round trips — in MPG or L/100km with any currency fuel price.
• Currency Converter (Live Exchange Rates) — Convert amounts between 40+ world currencies at live mid-market rates — USD, EUR, GBP, BDT, INR, JPY and more — with the exact cross rate, inverse rate, and step-by-step math.
• EV Charging Cost Calculator (Home vs Public vs Gas) — Calculate what a charge really costs — battery size, start and end state of charge, charging losses, and your rate — with cost per mile, monthly charging spend, and annual savings versus gas.

⏱️ Date & Time Calculators

• Exact Chronological Age Calculator — Calculate exact age in years, months, days, total weeks, hours, minutes, and countdown to your next birthday.
• Time Duration & Difference Calculator — Calculate elapsed time duration, hours and minutes difference between two timestamps, and decimal hours.
• Live Weather Forecast & Radar Map Calculator — Real-time local weather forecasts, interactive live radar maps, hourly temperatures, UV index, sunrise/sunset, and heat index calculations.
• Business Days & Working Day Calculator — Count business days between two dates, exclude weekends and holidays, or add/subtract working days from a start date for project and payroll planning.
• Date Calculator - Add & Subtract Days — Add or subtract days, weeks, months, and years from any date, calculate the exact duration between two dates in days, weeks, and months, and find the day of the week for any date.
• Time Zone Converter — Convert a date and time between any world time zones including DST, show UTC offsets, and compare world cities side by side with live clocks.
• Work Hours Calculator (Shifts, Overtime & Pay) — Calculate daily and weekly work hours from shift start, end, and unpaid breaks, with overtime over 40 hours and weekly, monthly, and yearly gross pay.
• Sleep Calculator (Bedtime & Wake-Up by Cycle) — Bedtime and wake-up times aligned to 90-minute sleep cycles, with cycle counts, sleep durations, and a 15-minute fall-asleep buffer in either direction.
• Unix Timestamp Converter (Epoch ⇄ Date & Time) — Convert epoch timestamps in seconds or milliseconds to UTC, ISO, and local time — and turn any date and time back into Unix seconds, with a live ticking now.
• Days Until Calculator (Countdown to Any Date) — Count down to Christmas, birthdays, weddings, exams, or any date — days, weeks, months, hours, and the day of week, with a past-date days-ago mode.

🌐 Network & Internet Calculators

• Live Internet Speed & Ping Test — Test real-time internet download speed, upload bandwidth, ping latency, jitter, and get gaming & 4K streaming ratings.
• Streaming & Data Usage Calculator — Calculate daily and monthly internet data consumption for YouTube, Netflix (4K/1080p), Spotify, Zoom, and monitor ISP monthly caps.
• IP Subnet & CIDR Calculator — Convert CIDR prefixes to subnet masks, find network address, broadcast address, first/last host, and total usable IPs for IPv4 and IPv6 ranges.
• Screen Size, Resolution & PPI Calculator — Calculate screen width and height from diagonal size and aspect ratio, find pixel density (PPI), and compare actual viewing area across monitors and TVs.
• Power Bank & Battery Capacity Calculator — Estimate power bank Wh capacity, usable energy after efficiency losses, and how many full device charges it delivers from mAh, voltage, and efficiency.
• Binary Converter (Binary, Decimal, Hex & Octal) — Live-synced binary, decimal, hexadecimal, and octal fields with bit-length, byte grouping, ASCII, and signed two's complement views for 8- and 16-bit values.
• Word Counter (Characters, Reading & Speaking Time) — Instant word, character, sentence, paragraph, and line counts with reading time at 200 WPM, speaking time at 130 WPM, and length averages — live as you type.
• Typing Speed Test (WPM & Accuracy) — Run 30, 60, or 120 second typing tests with live WPM, accuracy, and error tracking — then a final net WPM score using the standard 5-character word math.
• Password Generator (Strength & Entropy Meter) — Generate cryptographically strong passwords with length, symbol, and look-alike filters — entropy bits, pool size, strength rating, and offline crack time.
• Electricity Bill Calculator (kWh Usage & Cost) — Estimate monthly and annual electricity costs from appliance wattage and run time — kWh usage, rate per kWh, fixed charges and taxes, plus a per-device cost breakdown.
• AI Token Calculator (Words to Tokens & LLM API Cost) — Estimate tokens for any text, price input and output tokens per request with editable model rates, and project the monthly API bill — everything runs locally in your browser.

💪 Health & Fitness Calculators

• BMI & BMR Calorie Calculator — Calculate BMI with WHO categories, BMR (Mifflin-St Jeor), daily calorie needs (TDEE), and weight-goal targets.
• Body Fat Percentage & Ideal Weight Calculator — Estimate body fat percentage with the US Navy circumference method, classify it by sex and age, and find ideal body weight with the Devine formula.
• Daily Water Intake Calculator — Calculate your daily water intake needs in liters, ounces, and cups based on body weight, activity level, climate, and pregnancy or breastfeeding status.
• Macro Calculator - Protein, Carbs & Fat Split — Split daily calories into protein, carbohydrate, and fat grams using body-weight ratios or percent splits, with meal-by-meal targets for cut, maintain, and bulk goals.
• Running Pace & Race Time Calculator — Calculate running pace per kilometer and mile, average speed, split times for 5K, 10K, half marathon, and marathon, and predicted race times from any recent effort.
• Pregnancy Due Date Calculator (Naegele's Rule) — Estimate your baby's due date from the last menstrual period or conception date using Naegele's rule, with gestational age, trimester timeline, and cycle-length adjustment.
• Ideal Weight Calculator (Devine, Robinson, Miller, Hamwi) — Find your ideal weight with the Devine, Robinson, Miller, and Hamwi formulas from height and sex, plus the healthy BMI weight band and current-weight comparison.
• Ovulation Calculator (Fertile Window & Cycle Dates) — Find your ovulation date, six-day fertile window, cycle status, and the next five period dates from your last period, cycle length, and luteal phase.
• Weight Loss Calculator (Goal Date & Calorie Deficit) — Turn a goal weight and weekly loss rate into a target date, required daily calorie deficit, pace-safety check, and BMI at your goal weight.
• TDEE Calculator (Daily Calories & Cut/Bulk Targets) — BMR via Mifflin-St Jeor, activity multiplier, and maintenance calories — then cut or bulk targets with weekly change projections and a safe-floor check.
• Steps to Miles Calculator (Stride & Distance) — Convert steps into miles or kilometers from your stride length, with walking time at your pace and steps-per-mile math for any daily step goal.
• BAC Calculator (Blood Alcohol Level & Sober Time) — Estimate blood alcohol concentration from standard drinks, body weight, sex, and elapsed time using the Widmark formula — with hours to zero and legal limit context.