All calculators

Estimate quarter-mile elapsed time and trap speed from vehicle weight and horsepower.

Estimate a 14k gold ring's melt value from weight in grams and gold price per troy ounce. Excludes stones and resale premiums; no live gold prices.

Estimate your one-rep max.

Project retirement savings.

Magnitude and distance on the number line.

From velocity and time.

Score all six ACFT events, check the 60-point minimum per event and see your total out of 600.

Area in acres from dimensions.

Convert raw ACT correct answers into scaled section scores and a composite, with rounding rules explained.

Shift a date by days, weeks, months or years.

Estimate AdsTerra earnings from pageviews, CPM rates and ad formats, with geography and fill-rate effects explained.

Estimate video ad revenue from views, fill rate and video CPM, including completion-rate effects.

Estimate AdThrive (Raptive) earnings from sessions and RPM, and see what drives premium display rates.

Estimate affiliate earnings from traffic, click-through rate, conversion rate and commission, including EPC.

Exact age in years, months, days.

Solve algebraic equations for x, with the balancing steps shown so you can follow the method rather than just the answer.

Compare Big O complexity classes by input size and see how many operations each costs as n grows.

Calculate true landed cost on Alibaba imports including freight, duty, VAT and inspection, then work out your margin.

Calculate dropshipping profit from AliExpress including product cost, shipping, payment fees, ads and refunds.

Calculate FBA profit per unit after referral fees, fulfilment fees, cost of goods and shipping.

Estimate Amex high-yield savings interest from your balance, APY and years. Compare fixed-rate scenarios; enter the current rate yourself. No live bank rates.

Full payment schedule.

Degrees, radians, gradians and DMS.

Calculate annual leave entitlement, pro-rata days for part-year starters and accrual to date for part-time staff.

Accumulation value of regular deposits.

Sustainable income from a balance.

Work out whether your request volume fits an API rate limit, including burst capacity and required backoff.

Annual Percentage Yield.

Arc and chord from radius and angle.

Square feet, metres, acres, hectares.

Calculate the arithmetic mean of a data set alongside median and mode, and see when the average misleads.

Check below-the-zone promotion eligibility dates and time-in-grade requirements for early advancement.

Convert between ASCII characters and their decimal, hexadecimal and binary codes, with Unicode context.

Estimate 10-year atherosclerotic cardiovascular disease risk from cholesterol, blood pressure, age and risk factors.

Tonnage required for paving.

Estimate ATAR from scaled study scores, including the aggregate calculation and increments for extra subjects.

Calculate a car lease payment from capitalised cost, residual value and money factor, and convert money factor to APR.

See how your credit score changes an auto loan rate, monthly payment and total interest across the loan term.

Estimate Autopac-style vehicle insurance premiums from base rate, vehicle class, use and safe-driving discount.

Mean of any number list.

Arithmetic average versus true CAGR.

Convert moles to molecules with Avogadro's constant. Follow worked grams-to-moles and atoms-to-molecules examples, with units and particle types explained.

Estimate a monthly cloud bill from instance hours, storage volume and data transfer.

Estimate the probability of a baby's eye colour from both parents' eye colours, with the genetics explained.

Blood alcohol content and time to sober.

Payment and final balloon due.

Convert between connection speed, file size and transfer time, and estimate monthly bandwidth use.

Four operations with brackets and typed input.

Find support reactions, maximum bending moment and deflection for a simply supported beam.

Estimate your bench press one-rep max from a working set and get percentage-based training loads.

Base-2 conversion and arithmetic.

Exact and cumulative probabilities.

Body Mass Index from height and weight.

Daily calories burned at rest.

Calculate board feet from thickness, width and length, using nominal versus actual dimensions, and price hardwood by the board foot.

Long-term marine financing costs.

Estimate body fat percentage from tape measurements using the US Navy circumference formula.

Determine your body frame size from wrist circumference and height, and see how it adjusts ideal weight ranges.

Calculate body surface area in m² using the Mosteller and Du Bois formulas for clinical dosing reference.

Calculate a bond's current yield and approximate yield to maturity from price, coupon and time remaining.

Where your take-home pay actually goes.

Working days excluding weekends and holidays.

Term loan payments and total cost.

Daily calorie needs by goal.

MET-based energy cost of any workout.

Long-term and short-term tax on a sale.

Work out car loan monthly payments, total interest and the effect of a deposit or trade-in.

Which car incentive wins.

Convert your cat's age into human years using the standard feline life-stage scale, with senior care guidance.

Certificate of deposit maturity and APY.

Cumulative GPA across every term.

Area, circumference and diameter.

Cash needed to close, itemised.

Check the contrast ratio between two colours against WCAG 2.1 AA and AAA thresholds.

Calculate combinations and permutations, with and without repetition, and see when order matters.

Tiered commission and total earnings.

Grow capital over time.

Likely conception day and fertile window.

Calculate concrete volume for slabs, footings and columns, with bag counts and a waste allowance.

Volume, slant height and surface area.

Intervals for means and proportions.

Cups to grams by ingredient.

Pearson r, r squared and covariance.

Days, hours and minutes remaining.

See how long a credit card balance takes to clear and how much extra payments save in interest.

Calculate crypto trading profit or loss including exchange fees, break-even price and estimated capital gains tax.

Volume, surface area and diagonal.

Convert between currencies and see how spreads and transfer fees change the rate you actually receive.

Convert cycling speed, distance and ride time, and estimate how gradient and drafting change your average.

Tank and pipe capacity in litres.

Bytes, MB, GB, TB, MiB and GiB.

Days, weeks and calendar terms between dates.

Which weekday any date falls on.

Countdown to any future date.

Estimate your deadlift one-rep max from reps and weight, with percentage training loads and strength standards.

Does consolidating actually save money.

Plan a debt payoff schedule across multiple balances and compare the avalanche and snowball methods.

Front-end and back-end DTI for lenders.

Closest fraction within a denominator limit.

Density, mass or volume, plus specific gravity.

Straight-line, DDB and sum-of-years.

Numeric f'(x) and the tangent line.

Humidity comfort and condensation risk.

Sale price and savings.

Distance between points in 2D or 3D.

Calculate dividend yield, annual income and yield on cost, plus the payout ratio's sustainability signal.

Convert your dog's age into human-equivalent years using size-adjusted rates, not the old multiply-by-seven rule.

How much to save and how long it takes.

Transfer time from size and speed.

Calculate eBay selling fees, payment processing and net profit on a listing.

Work out the emergency fund you need from essential monthly costs and your income stability.

Joules, calories, kWh, BTU and therms.

Federal and state estate tax exposure.

Powers with negative and fractional exponents.

Interest and years saved by paying more.

Exact n! with big-integer precision.

Factor quadratic trinomials into linear factors.

Payment including upfront MIP.

Work out the score you need on a final exam to reach a target course grade.

Calculate the portfolio needed for financial independence from annual spending and a safe withdrawal rate.

Calculate flooring area, packs required and total cost including waste for laminate, vinyl or timber.

Newton's second law, F = ma.

Newtons, pounds-force, kilograms-force.

Add, subtract, multiply and divide fractions.

Work out the hourly rate that supports your target income once tax, overhead and unbillable time are counted.

Calculate the fuel cost of a journey or a year of driving from distance, efficiency and fuel price.

MPG, L/100km and km per litre.

What today's money becomes.

Estimate blockchain transaction fees from gas limit and gas price in gwei, converted into fiat currency.

Greatest common factor of any number list.

Handicap index and course handicap.

Weighted grade point average.

Convert GRE raw correct answers into 130–170 scaled Verbal and Quant scores, with percentile context.

Radioactive and first-order decay.

Calculate the five heart rate training zones from maximum or reserve heart rate, including the Karvonen method.

Apparent temperature and heat risk level.

Feet and inches to centimetres.

Estimate home equity line of credit payments during the interest-only draw period and the repayment period after it.

Hexadecimal conversion and arithmetic.

Fixed second-mortgage payments.

Calculate horsepower from torque and RPM, or estimate it from weight and quarter-mile trap speed.

Convert an hourly wage into weekly, monthly and annual pay, and back again.

The price your income really supports.

Longest side or a missing leg.

Solve PV = nRT for any variable.

Compare ideal body weight estimates from the standard clinical formulas and a healthy BMI range.

Estimate income tax across progressive brackets and see the difference between your marginal and effective rate.

Future prices and purchasing power.

Definite integrals by Simpson's rule.

Solve the rate behind any payment.

Plan a 16:8, 18:6 or 20:4 intermittent fasting schedule and see your exact eating window times.

Arcsin, arccos and arctan in degrees.

Growth from lump sum plus contributions.

Find the internal rate of return for a series of uneven cash flows and compare it to your hurdle rate.

Energy of a moving mass, plus momentum.

Third side and all angles.

Solve triangles from angles and a side.

Least common multiple of two or three numbers.

Calculate lean body mass from weight and body fat, plus fat-free mass index for comparison across heights.

Check any year against the Gregorian rules.

Compare the total cost of leasing against buying a car over the same period, including equity.

Metres, feet, inches, miles and more.

One-sided and two-sided limits.

Solve ax + b = c for x.

Least squares line and predictions.

Any installment loan, any term.

Any installment loan, any term.

LTV, combined LTV and equity.

Calculate logarithms in any base, including log₁₀, natural log and log₂, with the change-of-base method shown.

Quotient, remainder and every step shown.

A light-hearted compatibility score from two names and birth dates, with a note on what actually predicts relationship success.

Split a daily calorie target into protein, carbohydrate and fat grams based on your goal.

Price, margin and markup multiple.

Marriage penalty or bonus, quantified.

Perform matrix addition, multiplication, transpose, determinant and inverse operations with dimension rules explained.

Find your training zones.

Median, every mode, quartiles and IQR.

Centre point and perpendicular bisector.

Convert mixed numbers to improper fractions.

Molecular weight from a chemical formula.

Solution concentration in mol/L.

Total cash by note and coin denomination.

Monthly payment and total interest.

How fast extra payments clear the loan.

Calculate actual MPG or litres per 100 km from odometer readings and fuel added.

Calculate mulch volume in cubic yards and bags from bed area and depth, with settling and coverage guidance.

What expense ratios cost you.

Calculate net carbs from total carbohydrate, fibre and sugar alcohols, and set a ketogenic macro target.

Probability between any two values.

Discount future cash flows to today's value and see whether an investment creates or destroys value.

Solve for voltage, current, resistance or power from any two known values using Ohm's law.

Estimate your strict overhead press one-rep max and see typical ratios against bench press and bodyweight.

Estimate your ovulation date and six-day fertile window from your cycle length and last period start date.

Calculate paint quantity from wall area, number of coats and the coverage rate on the tin.

Measure password entropy in bits from length and character set, with estimated crack times.

Calculate how long an investment takes to repay its cost, in both simple and discounted terms.

Convert gross salary into take-home pay per pay period after tax, contributions and pre-tax deductions.

Defined benefit income and lifetime value.

Measured value against the accepted value.

Sale price and cash saved, including stacked deals.

All percentage operations.

Percent change between any two values.

Payment and true cost with fees.

Mortgage insurance cost and removal date.

Real roots of cubics and quadratics.

Watts, kilowatts, horsepower, BTU/hr.

Estimate a due date from a last menstrual period or conception date, with trimester milestones.

IOM targets by week and BMI.

What future money is worth today.

PSI, bar, kPa, atmospheres, mmHg.

Break any number into its prime factors.

Calculate probabilities for single and multiple events, including union, intersection, complement and conditional probability.

Solve A/B = C/D for the missing term.

Calculate daily protein needs from body weight, activity level and whether you are building or cutting.

Solve for the hypotenuse or either leg of a right triangle, with area, perimeter and angles included.

Solve ax² + bx + c = 0, with the discriminant, real or complex roots, and the vertex.

5K to marathon equivalent times.

Draws with or without repeats.

Simplify ratios and scale them up.

Estimate how long a text takes to read from word count and reading speed.

Work out whether refinancing your mortgage pays off, including closing costs and the break-even month.

Area, apothem and interior angle.

True cost of renting against owning.

Cash flow, cap rate and cash-on-cash.

Calculate the required minimum distribution from a retirement account using the IRS life expectancy factor.

Decode resistor colour bands into resistance, tolerance and temperature coefficient.

Hypotenuse, angles and area.

Find your ring size from finger circumference or inner diameter, with US, UK, EU and Japanese conversions.

Calculate return on investment as a percentage, plus the annualised return that makes holding periods comparable.

Numbers to Roman numerals and back.

Calculate roof area from footprint and pitch, convert to squares, and work out shingle bundles including waste.

Project Roth IRA growth with annual contributions and compare after-tax outcomes against a traditional IRA.

Compare four rounding rules side by side.

Years to double your money.

Convert between running pace, distance and finish time, with equivalent race time predictions.

Add sales tax or VAT to a net price, or extract the tax already included in a gross figure.

Responses needed for a target margin.

Convert practice test raw scores into estimated SAT section and total scores.

Work out the monthly saving needed to hit a target by a date, with interest growth included.

Trigonometry, logs, powers, roots and pi.

Standard, engineering and expanded forms.

Pie slice and circular segment area.

Arithmetic and geometric terms and sums.

Convert an uptime percentage into permitted downtime per day, month and year.

Convert shoe sizes between US, UK, EU and centimetres from your foot length, with width and fit guidance.

Calculate Shopify store profit after COGS, transaction fees, shipping, apps, ads and refunds.

Count sig figs and round correctly.

The plainest keypad for quick everyday sums.

Interest without compounding.

Find bedtimes and wake times aligned to 90-minute sleep cycles, allowing for time to fall asleep.

Gradient, intercept and line equation from two points.

See how claiming social security early or late changes your monthly benefit and lifetime total.

MPH, KPH, knots, m/s and Mach.

Volume and surface area from radius.

Square roots, cube roots and perfect squares.

Estimate your back squat one-rep max from reps and weight, with training loads and depth considerations.

Estimate staking rewards over time, converting APR to APY with compounding and accounting for validator commission.

Calculate standard deviation and variance for a sample or a full population, with the working shown.

Calculate profit or loss on a share trade including commissions, and the break-even sale price.

Estimate monthly cloud storage costs including capacity, request charges, egress and storage class tiering.

Calculate processing fees and net payout on a card payment, including the amount to charge to net a target.

Repayment schedule and lifetime interest.

IPv4 network, mask, range and hosts.

Find your suit jacket size from chest measurement, understand jacket drop, and convert between US, UK and EU sizing.

Evaluate sigma-notation series.

Box area, volume and space diagonal.

Convert swim times into pace per 100 m or 100 yd, plan splits and estimate critical swim speed.

Two simultaneous equations, solved by determinants.

Net pay after tax and deductions.

Estimate the calories you burn per day from BMR and activity level, and set a deficit or surplus.

Celsius, Fahrenheit, Kelvin, Rankine.

Calculate how many tiles and boxes you need for a floor or wall, including cuts and pattern waste.

Weekly hours, overtime and gross pay.

Hours between two clock times.

Seconds, minutes, hours, days, years.

Convert a time between zones, allowing for daylight saving on the date you choose.

Split bills and work out the tip.

Compare tyre sizes for overall diameter, circumference, revolutions per mile and speedometer error.

Calculate torque from force and lever length, or from power and rotational speed.

Newton-metres, pound-feet, pound-inches.

Check safe towing capacity using GCWR, GVWR, payload and tongue weight limits before you hitch up.

Area and median from parallel sides.

Discount rate and bond equivalent yield.

Base-height and Heron's formula.

Sine, cosine and tangent, either unit.

Estimate Twitch streaming income from subscriptions, bits, ads and donations, with the standard revenue splits applied.

Calculate typing WPM from characters and elapsed seconds, plus a word-error accuracy estimate. Includes a worked example; not a timed typing test.

Convert between metric and imperial units for length, weight, volume, area, speed and temperature.

Epoch time to date and back.

Zero-down payment with funding fee.

Sample and population variance.

File size, bitrate and upload time.

Estimate VO2 max from race times, resting heart rate or field tests, with fitness category ranges.

Calculate voltage drop over a cable run from current, length and conductor size, and check it against limits.

Litres, gallons, cups and cubic feet.

Calculate waist-to-hip ratio and waist-to-height ratio, and interpret them against WHO risk thresholds.

Better risk screen than BMI.

Estimate daily fluid needs from body weight, activity, climate and what food already provides.

Frequency, wavelength and photon energy.

ISO 8601 week of the year.

Kilograms, pounds, stones and tons.

Course grade from weighted components.

Feels-like cold and frostbite risk.

Estimate YouTube earnings from views, RPM and CPM, including the 55/45 revenue split and monetised playback rate.

Standard score, percentile and p-value.

Find your zodiac sun sign from your birth date, with element, modality and cusp date explanations.