Standard arithmetic with memory, percent and scientific helpers.

Full scientific calculator: trig (deg/rad/grad), hyperbolic, log/ln, factorial, nCr/nPr, fractions, scientific/engineering modes, memory and history.

Loan EMI with down payment, processing fee, moratorium, prepayment, floating rate and loan comparison.

Multi-mode loan calculator: home, auto, personal, student. APR, amortization, prepayment, refinance compare and tax benefits.

Mortgage EMI with property tax, insurance, PMI, prepayment, refinance compare and tax benefit.

Auto loan with sales tax, registration, down payment, APR, amortization and prepayment.

Personal / business loan with processing fee, APR, amortization, prepayment and comparison.

Simple interest with multi-unit time, solve-for any variable, schedule, comparison and export.

Compound interest with SIP/step-up, tax, inflation-adjusted real return, goal planner, comparison and CAGR.

Fixed Deposit maturity, post-tax value, senior bonus, payout modes, premature withdrawal and inflation-adjusted return.

Recurring Deposit maturity with step-up, missed months, senior bonus, tax, TDS and full year-wise schedule.

SIP, lump-sum, SIP+lump, SWP and Goal planner with step-up, inflation, LTCG tax, XIRR, schedule and comparison.

WHO BMI, new Trefethen BMI, ponderal index, healthy range, weight-to-goal and full WHO categories.

Mifflin-St Jeor, Harris-Benedict and Katch-McArdle BMR + TDEE and full calorie goal table.

Daily calorie goal with macros (balanced, low-carb, high-protein, keto) and zigzag schedule.

Robinson, Miller, Devine, Hamwi and healthy BMI weight range with metric/imperial.

US Navy method + BMI method body fat %, fat mass, lean mass, categories and ideal range.

Daily water need with age, climate, activity and pregnancy adjustments + hourly schedule.

Due date from LMP, conception, ultrasound or IVF transfer with trimester and milestones.

Exact age in years/months/days, next birthday, zodiac, generation, life-progress, retirement countdown and compare ages.

Full mortgage payment with PITI: principal, interest, property tax, insurance, PMI, HOA, extra payments and amortization.

Simple & compound interest with contributions, multiple compounding, tax, inflation and growth chart.

Solve for monthly payment or term: enter any two of amount, rate, term, payment.

Retirement corpus, gap analysis, monthly income, step-up contributions, inflation and life-expectancy planning.

Full amortization schedule with extra payments, biweekly option, yearly/monthly view and interest savings.

Future value of investments with SIP, step-up, tax, inflation-adjusted return and CAGR.

Future value, past-to-today and purchasing-power calculations with year-by-year chart.

Time-Value-of-Money solver: compute PV, FV, PMT, N or Rate from the other four.

Multi-country income tax: USA, India (new/old), UK, Canada, Australia, Bangladesh with slabs, take-home and effective/marginal rate.

Sales Tax, VAT, GST with 30+ regional presets: add/remove tax, reverse solve, multi-item cart, margin pricing, rate comparison, discounts, shipping and rounding.

Solve for pace, time or distance. Splits per km/mile, kph/mph, calories, distance presets (5K, 10K, half, marathon, ultra) and full schedule.

Multi-segment pace tracker: add unlimited splits with per-segment distance/time, get cumulative time, per-segment pace, average pace and pace chart.

Convert between min/km, min/mile, kph and mph — with per 100 m / 400 m / 800 m / mile splits and projected race times for 5K, 10K, half and marathon.

Project live race finish time from current pace plus a Riegel race-time predictor across 5K, 10K, half, marathon and ultra distances.

Full fraction suite: add/subtract/multiply/divide/power, mixed numbers, simplify, decimal↔fraction (with repeating detection), big-number (BigInt), multi-operand expressions, compare/sort, step-by-step solutions.

All-in-one percentage: X% of Y, X is what % of Y, % change, increase/decrease, add/subtract %, tip — with step-by-step working.

Percent error, accuracy, absolute and relative error with full formula walkthrough.

Compute a^n with expansion, negative & fractional exponents, scientific notation and exponent rules.

Logarithm in any base with change-of-base, log₁₀, ln and step-by-step verification.

Square root, cube root, n-th root with real/complex handling and verification.

Solve ax²+bx+c=0: real & complex roots, discriminant, vertex, axis of symmetry, factored form.

Solve any of N₀, N(t), t, t½. Decay constant λ, mean lifetime τ and decay curve chart.

Convert to/from scientific & engineering notation and perform calculations with very large/small numbers.

Simplify, solve equivalent ratios (A:B = C:D), scale by factor, convert to decimal and percentage.

Least common multiple of N numbers using prime factorisation with full breakdown.

Greatest common factor (GCD) with Euclidean algorithm step-by-step and LCM cross-check.

All factors, factor pairs, prime factorisation, sum of factors and primality check.

Round to decimal places, significant figures or nearest unit using half-up, banker's, ceil, floor, truncate or away-from-zero.

Matrix add, subtract, multiply, scalar, transpose, determinant and inverse with trace and properties.

Generate random integers or decimals with min/max, count, unique mode, optional seed and full stats summary.

Binary arithmetic (+ − × ÷), bitwise AND/OR/XOR, shifts, plus instant decimal/hex/octal conversion.

Hexadecimal arithmetic and bitwise ops with universal base-2/8/10/16 converter.

Unlimited-precision integer arithmetic (BigInt): +, −, ×, ÷ with remainder, mod and exponent.

US Army AR 600-9, USMC and US Navy circumference method with age-based max allowable BF and pass/fail status.

Boer, James, Hume, Peters and direct-from-bodyfat lean mass with cross-formula average.

WHO BMI healthy range plus Robinson, Miller, Devine, Hamwi and age-adjusted ideal weight with ponderal index.

MET-based calories burned for 40+ activities (running, cycling, swimming, gym, sports, daily chores) — multi-select with totals.

Estimate 1RM with Epley, Brzycki, Lander, Lombardi, Mayhew, O'Conner and Wathan plus full % of 1RM training table.

Max HR (Fox / Tanaka / Gulati) and Karvonen 5-zone training ranges using heart rate reserve.

Macros from daily calories with Balanced, Low-Carb, High-Protein, Keto, Zone, Mediterranean or fully custom split + fiber/water/sugar targets and per-meal breakdown.

Daily carb target by % of calories AND g/kg body weight — sedentary to ultra-endurance with fiber and net-carb breakdown.

Daily protein range for sedentary, active, endurance, strength, cut, bulk, senior or pregnant — with per-meal split and food references.

Total fat g from kcal with saturated, trans, mono, poly, omega-3 and omega-6 targets per AHA / IOM guidelines.

Total Daily Energy Expenditure with Mifflin-St Jeor, Harris-Benedict and Katch-McArdle BMR plus 6 calorie goal tiers.

Glomerular filtration rate using CKD-EPI 2021 (race-free), MDRD, Cockcroft-Gault and Schwartz (pediatric) with KDIGO CKD stage.

Ectomorph / Mesomorph / Endomorph somatotype from height-to-wrist ratio plus frame size and McCallum ideal measurements.

BSA via Du Bois, Mosteller, Haycock, Gehan-George, Boyd and Fujimoto formulas with cross-formula average.

Blood Alcohol Content using Widmark and Watson TBW with multi-drink list, presets, food adjustment, hours-to-sober and legal-limit status.

Add/subtract years, months, weeks and days from a date OR get the full difference between two dates in y/m/d, weeks, hours and minutes.

Add and subtract multiple hours/minutes/seconds values with running total in h:m:s, decimal hours and minutes.

Hours between two times with break deduction, decimal hours, regular vs overtime split and gross pay estimate.

Full weekly timesheet (Mon–Sun) with in/out/break per day, 40-hr OT split and gross pay at your hourly rate.

Convert any date/time across 20 major world time zones with a live world-clock reference table.

Exact duration between two date-times in days/hours/min/sec plus totals in each unit.

Count days between two dates with optional weekend exclusion and business-day total.

Find the weekday for any date plus day-of-year, ISO week number and leap-year status.

Concrete volume for slabs, footings, columns and stairs in cubic yards, feet and meters with 60-lb and 80-lb bag counts.

Heating/cooling BTU/hr for a room based on area, climate zone, sun exposure, occupants and kitchen load — with tons and kW.

Area of rectangle, triangle, circle and trapezoid in sq ft, sq yd, sq m and acres.

Riser count, riser height, total run, stringer length and stair angle from total rise — with IRC building-code check.

Actual roof area from footprint and pitch, with waste %, squares and shingle bundle count (3 bundles per square).

Tile count for any room including grout gap, waste % and total cost.

Mulch volume in cubic yards / feet / tons plus 2-cu-ft bag count and total cost.

Gravel volume in cubic yards / feet / tons plus bag count and total cost.

Predicted adult height using the mid-parental (Tanner) formula with ±8.5 cm 95% range in cm and inches.

Universal unit converter — length, mass, volume, area, time, speed, energy, pressure, data and temperature.

GDP via expenditure (C+I+G+NX), income approach, nominal/real growth and GDP per capita.

Solve ρ = m / V for density, mass or volume with reference densities for water, metals and gases.

Solve m = ρ × V for mass, density or volume.

Weight (W = m × g) on Earth, Moon, Mars and every planet in N, kgf and lbf.

Solve s = d / t for speed, distance or time with km/h, m/s, mph and knot output.

Molarity (M = moles / L) — solve for concentration, mass or volume with dilution (M₁V₁ = M₂V₂).

Parse any chemical formula (incl. nested parentheses) to compute molecular weight and per-element mass percent.

Two-way converter: Arabic ↔ Roman (1–3999) with full cheat sheet of subtractive pairs.

NEC voltage drop for copper or aluminum, AWG 14 to 4/0, single- or three-phase with % drop and code compliance.

4-band and 5-band color-code resistor decoder plus series and parallel resistance calculator.

Enter any 2 of V, I, R, P — the rest auto-fill using Ohm's law and power formulas.

Multi-appliance kWh & cost calculator: watts × hours × qty per item with daily / monthly / yearly totals at your rate.

IPv4 subnet with CIDR: network, broadcast, mask, wildcard, host range, class, public/private and binary view.

Cryptographically secure password generator with length, character sets, exclude similar, bulk count and entropy strength meter.

Solve for transfer time, transferable size, or required speed across MB/GB/TB and Kbps/Mbps/Gbps.

Encode and decode Base64 text with one-click swap, UTF-8 safe.

Percent-encode and decode URLs and URL components with full/component mode.

Weighted 4.0-scale GPA with unlimited courses, credits, letter grades and grade points.

Weighted current grade plus target-grade planner: what you need on the rest to reach your goal.

US / UK / EU bra size from band and bust measurements in inches or centimeters.

Convert shoe sizes across US, UK, EU and centimeters for men and women.

Tip and split with preset 10/15/18/20/25%, round up/down and per-person totals.

USGA-style handicap index from up to 20 rounds with course rating, slope and best-N differentials × 0.96.

Optimal bedtimes or wake times based on 90-minute REM cycles plus 15-minute fall-asleep buffer.

NWS 2001 wind chill in °F/mph or °C/km/h with frostbite risk indicator.

NWS Rothfusz heat index in °F with humidity, danger level and °C conversion.

Dew point via Magnus-Tetens in °C and °F with humidity comfort rating.

Trip fuel and dollar cost with US (mi/MPG/$gal) or Metric (km/L100/$L) modes plus daily/weekly/monthly/yearly totals.

MPG, km/L and L/100km from miles driven and gallons used.

Horsepower from quarter-mile ET, trap speed or torque × RPM with kW conversion.

Flywheel/crank HP estimate from wheel HP using FWD/RWD/AWD drivetrain loss factor.

IRS mileage reimbursement with business / medical / charity rate presets.

Tire diameter, sidewall, circumference and revolutions per mile from W/A/R sidewall code.

Roll up to 100 dice with any number of sides (d4–d100) using crypto-secure randomness with totals and stats.

Fun deterministic compatibility score from two names with a verdict and animated heart bar.

Final price after % off + flat coupon + tax. Stack two discounts or apply the best, with a savings breakdown and common-discount table.

Solve for selling price, markup % or cost. Compares markup vs margin with a full conversion table.

Gross / operating / net margin from revenue, COGS, opex and tax — with full income statement and markup view.

Total ROI, annualised return, money multiple, doubling time and comparison vs savings / FD / S&P 500 / equity benchmarks.

US take-home pay with 2024 federal brackets, FICA, state tax, 401(k) and health pre-tax — annual, monthly, bi-weekly and hourly net.

Convert hourly ↔ daily ↔ weekly ↔ bi-weekly ↔ monthly ↔ annual pay with vacation, holidays and work-hour adjustments.

Public Provident Fund maturity with year-wise deposit / interest / balance schedule for 15-, 20- or 25-year tenure.

Predict ovulation day, 6-day fertile window, next period and pregnancy due date from your LMP, cycle length and luteal phase.

Mean, median, mode, variance, SD (sample or population), quartiles, IQR, range, geometric & harmonic mean and coefficient of variation.

P(A∪B), P(A∩B), conditional probability, independence, nCr / nPr / n^k / n!, plus normal-distribution Z-score tail probabilities.

Add or remove GST/VAT (any rate) with net, tax, gross, CGST+SGST split, currency picker and a common-rate comparison table.

Payoff time and total interest for credit-card debt — minimum-only, fixed amount, or pay-off-in-N-months modes with extra-payment savings.

Profit/loss on a stock trade with commissions, capital gains tax, ROI, CAGR and break-even sell price.

Real-estate cap rate, NOI, cash-on-cash return, monthly cash flow, DSCR, GRM and the 1% / 50% rules in one tool.