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Everyday maths & percentages Money & planning Home & DIY Mathematics Units & converters Physics
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Everyday maths & percentagesPercentage calculatorCalculate a percentage amount, percentage rate or original whole. First choose which value you want to find.
Everyday maths & percentagesPercentage change calculatorCompare two values or apply a percentage change to an original value. For two percentages, also see the difference in percentage points.
Everyday maths & percentagesDiscount calculatorCalculate the final price and savings from one discount or two successive discounts.
Everyday maths & percentagesUnit price calculatorCompare two packs using the same quantity unit and find the lower price per unit.
Money & planningMargin and markup calculatorDistinguish profit margin, based on the selling price, from markup, based on purchase cost.
Money & planningCompound interest calculatorCalculate a future balance from an initial deposit, monthly contributions and an assumed constant interest rate.
Money & planningLoan repayment calculatorCalculate a fixed monthly payment, total repayments and interest for an amortising loan.
Money & planningSavings goal calculatorFind the monthly contribution needed to reach a target, taking your existing balance into account.
Money & planningCAGR calculatorCalculate the constant compound annual growth rate between an initial and a final value.
Money & planningInflation and purchasing power calculatorEstimate how prices and purchasing power change over time using your own constant inflation assumption.
Money & planningDividend yield calculatorCompare an annual dividend with the share price and calculate the estimated payout for your holding.
Money & planningPayback period calculatorEstimate when an initial investment is recovered through a constant annual net benefit.
Money & planningEffective annual rate calculatorConvert a nominal annual interest rate with multiple compounding periods into a mathematical effective annual rate.
Money & planningMonthly or annual subscription?Compare monthly payments with an annual subscription and find the usage break-even point.
Money & planningHousehold budget calculatorCompare monthly income with fixed costs, variable spending and your planned savings.
Marketing & businessROAS and marketing ROI calculatorCompare attributed revenue with advertising spend and include your own contribution margin before advertising.
Marketing & businessBreak-even calculatorFind the sales quantity and revenue needed to cover fixed costs at a constant contribution per unit.
Marketing & businessBreak-even ROAS calculatorFind the ROAS needed to cover advertising spend at your contribution margin.
Marketing & businessCPC calculatorCalculate cost per click using related advertising data from the same period.
Marketing & businessCPM calculatorCalculate cost per thousand impressions using related advertising data from the same period.
Marketing & businessCPA calculatorCalculate cost per recorded conversion using related advertising data from the same period.
Marketing & businessClick-through rate calculatorCalculate clicks as a percentage of impressions using related data from the same period.
Marketing & businessConversion rate calculatorCalculate recorded conversions as a percentage of visits using related data from the same period.
Marketing & businessAverage order value calculatorCalculate revenue per order over your chosen period using related data.
Marketing & businessCapacity utilisation calculatorCompare used capacity with available capacity over the same period.
Marketing & businessCart abandonment rate calculatorFind the proportion of started shopping carts that did not result in a completed order.
Marketing & businessMeeting cost calculatorEstimate the working time and cost of a meeting from its participants, duration and your own hourly cost.
Marketing & businessCash runway calculatorCalculate how long an available cash balance lasts at a constant monthly net outflow.
Cars & travelFuel cost calculatorCalculate fuel required, total trip cost and each person's share using your own prices.
Cars & travelFuel consumption calculatorFind average fuel consumption from the distance driven and the fuel used.
Cars & travelEV range and trip cost calculatorEstimate range and energy use from usable battery capacity, consumption and your own electricity price.
Cars & travelEV charging time and cost calculatorEstimate energy, ideal charging time and cost between two battery charge levels.
Cars & travelTaxi fare calculatorEstimate a trip using your own starting fare, price per kilometre and waiting-time charge.
Home & DIYPaint calculatorEstimate paint quantity from the surface area, number of coats, manufacturer coverage and an allowance.
Home & DIYTile calculatorCalculate tile coverage and whole packs with your chosen waste allowance and pack size.
Home & DIYLaminate flooring calculatorCalculate the number of flooring packs with your chosen waste allowance and pack size.
Home & DIYPaving calculatorCalculate paving area and whole packs with your chosen waste allowance and pack size.
Home & DIYTurf calculatorCalculate the rolls needed for a lawn with your chosen waste allowance and roll size.
Home & DIYConcrete calculatorEstimate the concrete volume for a rectangular slab and its material cost using your own price.
Home & DIYAggregate calculatorCalculate loose volume, estimated mass and material cost for a layer over an area.
Home & DIYGravel calculatorCalculate loose volume, estimated mass and material cost for a layer of gravel over an area.
Home & DIYSoil calculatorCalculate loose volume, estimated mass and material cost for a layer of soil over an area.
Home & DIYMulch calculatorCalculate loose volume, estimated mass and material cost for a layer of mulch over an area.
Home & DIYGrass seed calculatorCalculate seed quantity from the area, the application rate on the pack and your allowance.
Home & DIYHedge plant spacing calculatorFind the number of plants needed along a length at your preferred maximum spacing.
Home & DIYSlope and gradient calculatorCalculate gradient in percent, slope angle and sloping length from a height difference and horizontal distance.
Home & DIYWallpaper calculatorEstimate rolls from wall width, wall height, roll size and an allowance for each strip.
Energy & waterElectricity cost calculatorCalculate an appliance's electricity use and cost with your own energy price.
Energy & waterWater use and cost calculatorConvert daily water use into monthly and annual quantities using your own combined water and wastewater price.
Energy & waterShower water cost calculatorEstimate water use and water/wastewater costs from flow rate, shower length and frequency.
Energy & waterLED savings and payback calculatorCompare two power levels at the same usage and estimate when the extra purchase cost is recovered.
Energy & waterHousehold bills calculatorAdd monthly electricity, water, heating and other regular household costs.
Date & timeDays between datesCalculate calendar days between two dates, with an option to include both endpoints.
Date & timeAdd days to a dateAdd or subtract calendar days and see the resulting date and day of the week.
Date & timeAge calculatorFind completed years of age and elapsed calendar days between a birth date and a reference date.
Date & timeDay of the week calculatorFind the day of the week for a date in the Gregorian calendar.
Date & timeISO week number calculatorFind the ISO week number, its week-year and the Monday of that week.
Date & timeTime duration calculatorCalculate a duration from start and end times. An earlier end time is treated as occurring on the following day.
Date & timeHours and minutes converterConvert hours, minutes and seconds into decimal hours and a total number of minutes or seconds.
Cooking & bakingRecipe scaling calculatorScale an ingredient quantity from the original number of servings to the number you need.
Cooking & bakingRound cake tin converterAdjust an ingredient quantity for a round tin with a different diameter while keeping the filling depth the same.
Cooking & bakingDough hydration calculatorCalculate the water-to-flour ratio and the total mass of flour, water and salt.
Cooking & bakingPizza dough calculatorSplit your desired total dough mass into flour, water, salt and yeast.
Cooking & bakingCost per serving calculatorCalculate a cost per serving from ingredient costs, other costs and the number of servings.
Cooking & bakingFresh and dry yeast converterConvert between fresh and dry yeast using a conversion factor you choose.
MathematicsFraction calculatorAdd, subtract, multiply or divide two fractions. The simplified result remains exact even with large numerators.
MathematicsGCD, LCM and prime factorsFind the greatest common divisor, least common multiple and prime factors of up to twelve whole numbers.
MathematicsRegular polygon calculatorCalculate area, perimeter, interior angles, inradius and circumradius from the number of sides and side length of a regular polygon.
MathematicsPolygon area from coordinatesEnter the vertices in order around the boundary to calculate the area, perimeter and centroid of a simple polygon.
MathematicsLinear interpolationFind an intermediate value from two known points. Outside their range, the calculator identifies the result as extrapolation.
MathematicsQuadratic equation solverSolve a·x² + b·x + c = 0. Real or complex roots, the discriminant and the vertex are shown separately.
MathematicsCubic equation solverCalculate the real and complex roots of a·x³ + b·x² + c·x + d = 0 and the coefficients of the depressed cubic.
MathematicsTriangle from three sidesFind the area, perimeter, angles, inradius and circumradius from three sides. The calculator checks the triangle inequality.
MathematicsCircle, sector and segmentCalculate circle area and circumference, plus the arc, chord and segment for your chosen central angle.
MathematicsCylinder calculatorCalculate the volume, lateral area, closed surface area and axial section of a right circular cylinder.
MathematicsCone and conical frustumCalculate volume, slant height and surface area. An upper radius of zero gives a complete cone.
MathematicsSphere calculatorFind the volume, surface area, diameter and great-circle area of a sphere from its radius.
MathematicsRectangular pyramid calculatorCalculate volume, lateral area, total surface area and slant heights of a right pyramid with a rectangular base.
MathematicsSquare pyramid frustumCalculate the volume, lateral area and total surface area between two aligned, parallel square bases.
MathematicsPythagorean theorem calculatorCalculate the hypotenuse from two legs, or find a missing leg from the hypotenuse and the known leg.
MathematicsLinear equation system solverSolve two or three equations together. The calculator distinguishes a unique solution, contradictions and free variables.
MathematicsExponential and logarithmic equationsSolve b^(a·x+c)=d or log_b(a·x+c)=d using your coefficients, with checks on the domain conditions.
MathematicsArithmetic and geometric sequencesCalculate the nth term, the sum of the first n terms and a preview from the first term and the difference or ratio.
MathematicsTwo points and their lineCalculate the distance, midpoint, slope and intercept of the straight line defined by two points.
MathematicsVector calculator in two or three dimensionsCalculate sums, differences, magnitudes, dot products and angles. Three-dimensional vectors also show the cross product.
MathematicsCombinatorics calculatorCount selections with or without order and repetition. Large counts are returned as exact whole numbers.
MathematicsStatistics and binomial probabilityDescribe a list with its mean, median and spread, or calculate the probability of a specified number of successes.
MathematicsSample size for a proportionPlan the valid responses and invitations needed from your margin of error, confidence level and expected response rate.
MathematicsProportion and Wilson intervalCalculate a two-sided Wilson confidence interval from successes and total observations, including observed proportions of 0% or 100%.
MathematicsBayes calculator with frequenciesCombine a prior proportion with an observed feature. Expected frequencies per 10,000 cases help you check the conditional probability.
MathematicsDrawing without replacementCalculate the probability that a random selection contains at least or exactly k topics you know.
MathematicsProbability of reaching a score by guessingCombine definitely correct answers with random guesses. Include points awarded, penalties and your target total score.
MathematicsCollecting stickers: new designs and duplicatesFor equally common designs, estimate the additional draws needed to complete a collection and the new designs and duplicates in a planned purchase.
MathematicsThree sets and their overlapsSplit counts for three groups into seven separate regions and find how many people lie outside all three groups.
MathematicsStatistics from grouped frequenciesEstimate the mean, standard deviation and median from class lower bounds, upper bounds and frequencies.
MathematicsJoint work timeCalculate how long two people or machines need to complete a task together, and what changes when B leaves early.
MathematicsTank filling and draining timeFind the time to a target level from two inflows, an outflow, total capacity and the current fill level.
MathematicsRound-robin matches and tournament durationPlan the match count and a conservative total duration for two to 24 teams, with multiple courts and breaks.
MathematicsReading and study time plannerPlan whole pages per day using your measured pace, an allowance for revision and regular study breaks.
MathematicsAttendance and absence allowanceCheck how many whole sessions you may miss and how many remain, using a course rule you enter yourself.
MathematicsRequired exam scoreCalculate the exam score needed to reach your target alongside your current result. An expected score shows the resulting overall mark.
MathematicsWeighted average and targetCalculate an average from scores and weights. An additional weight lets you find the new average needed to reach a target.
MathematicsMeasurement uncertainty propagationCalculate the combined standard uncertainty of a sum, difference, product or quotient of two independent measured quantities.
Digital toolsDownload time calculatorEstimate transfer time from file size, connection speed and the usable share of that speed. MB and MiB are treated separately.
Digital toolsPixel density and pixel pitch calculatorFind a display’s pixel density from its resolution and diagonal size. The result also shows pixel pitch, width and height.
Digital toolsPCM audio file size calculatorCalculate the storage needed for uncompressed audio from its duration, sample rate, bit depth and number of channels.
PhysicsDecibel ratio calculatorConvert a power or amplitude ratio into a level difference and see which logarithm rule applies.
PhysicsSound level and distance calculatorEstimate how the sound pressure level from a point source changes with distance.
PhysicsDistance from sound travel timeCalculate distance from the delay between lightning and thunder, or from the travel time of an echo.
PhysicsSimple pendulum period calculatorCalculate the period and frequency of an ideal simple pendulum at a small displacement.
PhysicsSpring oscillator: frequency and energyFind the period, frequency, energy and maximum speed of an ideal spring–mass oscillator.
PhysicsHydrostatic pressure calculatorFind the gauge pressure in a stationary liquid and add the ambient pressure to obtain absolute pressure.
PhysicsBuoyancy and submerged volumeCompare buoyant force with the weight of a closed body and estimate the submerged fraction when it floats.
PhysicsReynolds number for a circular pipeCalculate the dimensionless Reynolds number from density, mean speed, pipe diameter and dynamic viscosity.
PhysicsLinear thermal expansion calculatorCalculate the change in length of a freely expanding component after a temperature change.
PhysicsHeat conduction through a flat layerEstimate steady heat flow through a single homogeneous layer of material.
PhysicsTorque, rotational speed and powerCalculate the mechanical power of a rotating shaft from its torque and rotational speed.
PhysicsGear ratio and torque calculatorCalculate the ratio of two gears, together with the ideal output speed and torque.
EngineeringOhm’s law calculatorCalculate current and power from a DC voltage and an ideal ohmic resistance.
EngineeringElectric power from volts and ampsCalculate electric power from voltage and current for a DC circuit.
EngineeringCapacitor charge and energyCalculate the charge and electrical energy stored in an ideal capacitor.
EngineeringRC time constant and capacitor chargingCalculate capacitor voltage, charging current and the time constant after an ideal RC circuit is switched on.
EngineeringRL time constant and current riseFind the current rise in an ideal series circuit containing resistance and inductance.
EngineeringIdeal transformer calculatorCalculate the secondary voltage and corresponding primary current from the turns counts and secondary load.
ChemistryMass, moles and particle countConvert mass into an amount in moles and a particle count using the appropriate molar mass.
ChemistryMolarity of a solutionFind the amount concentration from the dissolved amount of substance and the final solution volume.
ChemistrySolution dilution: stock volume neededCalculate the stock solution volume needed for a target concentration and a specified final volume.
ChemistryPercentage yield calculatorCompare the product mass actually obtained with the theoretically possible mass.
ChemistrypH, pOH and approximate concentrationsCalculate pOH and approximate ion concentrations from pH and the assumed ionic product of water.
ChemistryBuffer pH: Henderson–HasselbalchEstimate buffer pH from pKₐ and the concentrations of a conjugate acid–base pair.
ChemistryIdeal gas pressure calculatorCalculate absolute gas pressure from amount of substance, volume and temperature using the ideal gas law.
PhysicsHeat energy from mass and temperature changeCalculate the heat energy needed for a temperature change at constant specific heat capacity.
ChemistryBeer–Lambert absorbance and transmittanceCalculate the absorbance of a homogeneous sample and the proportion of light transmitted through it.
Astronomy & opticsLight travel time in a vacuumCalculate the time light takes to travel a distance and compare one-way with round-trip travel.
Astronomy & opticsTelescope magnification calculatorCalculate magnification from telescope and eyepiece focal lengths, with an optional Barlow or reducer factor.
Astronomy & opticsTelescope exit pupil calculatorFind the diameter of the emerging light beam from aperture and magnification.
Astronomy & opticsTelescope true field of viewEstimate the visible patch of sky from the eyepiece’s apparent field of view and magnification.
Astronomy & opticsAngular size from size and distanceCalculate the angle subtended by a length perpendicular to the line of sight.
Astronomy & opticsAstrophotography image scale and field of viewCalculate arcseconds per pixel and the horizontal field of view from pixel size, sensor resolution and focal length.
Astronomy & opticsRedshift from wavelengthsCompare observed and emitted wavelengths to calculate the dimensionless redshift z.
Astronomy & opticsDistance modulus and apparent magnitudeCalculate apparent magnitude from absolute magnitude, distance and specified extinction.
Astronomy & opticsSimplified exoplanet transit depthEstimate the relative dimming during the full transit of a dark planet across a uniformly bright stellar disc.
Astronomy & opticsLuminosity and radiative fluxCalculate the power per unit area at a distance from a source emitting equally in all directions.
Astronomy & opticsPhoton energy, frequency and photon rateCalculate a photon’s energy and frequency from its vacuum wavelength, and the photon rate of monochromatic radiation.
Astronomy & opticsRefraction and total internal reflectionCalculate the refracted angle from refractive indices and the angle of incidence, and check for total internal reflection.
Astronomy & opticsThin lens: image distance and magnificationCalculate image position and magnification for an ideal thin lens and a real object.
Astronomy & opticsDiffraction angle of an optical gratingFind the angle of a diffraction order from wavelength and the line density of an ideal grating.
Astronomy & opticsDouble-slit interference fringe spacingEstimate the spacing of adjacent bright fringes near the centre of a double-slit pattern.
Units & convertersFuel consumption converterCompare fuel consumption in l/100 km, km/l, US MPG and imperial MPG. US and imperial gallons remain distinct.
Units & convertersTorque converterConvert torque between newton metres, newton centimetres, pound-force feet and other units.
Units & convertersVolume flow rate converterConvert flow rates per second, minute or hour, such as litres per minute to cubic metres per hour.
Units & convertersDensity converterCompare densities in kg/m³, g/cm³, kg/l and customary units under the same material conditions.
Units & convertersForce converterConvert force between newtons, kilonewtons, kilogram-force, pound-force and dynes.
Units & convertersAcceleration converterConvert acceleration between m/s², standard gravity gₙ and other length units per second squared.
Units & convertersAngular velocity converterConvert rotational speeds in rpm or revolutions per second to angular velocities in rad/s or degrees per second.
Units & convertersAngular acceleration converterConvert changes in angular velocity between rad/s², degrees per second squared and rpm/s.
Units & convertersDynamic viscosity converterCompare dynamic viscosities in pascal seconds, millipascal seconds, poise and centipoise.
Units & convertersKinematic viscosity converterConvert kinematic viscosity between m²/s, mm²/s, stokes and square feet per second.
Units & convertersTemperature difference converterConvert temperature changes and intervals in kelvin, Celsius, Fahrenheit or Rankine without a zero-point offset.
Units & convertersThermal conductivity converterPut thermal conductivities from material data sheets into the same unit, such as W/(m·K).
Units & convertersThermal resistance converterConvert thermal resistance between K/W, °C/W and °F·h/Btu. Area-specific R-values have a separate converter.
Units & convertersThermal insulance and R-value converterCompare area-specific thermal resistance in m²·K/W, US R-values, clo and tog.
Units & convertersSpecific heat capacity converterConvert specific heat capacity between J/(kg·K), kJ/(kg·K), thermochemical calories and Btu.
Units & convertersHeat flux converterConvert heat transfer rates per area between W/m², kW/m², W/cm² and Btu per hour per square foot.
Units & convertersHeat transfer coefficient converterConvert heat transfer coefficients between W/(m²·K), kW/(m²·K) and customary Btu units.
Units & convertersTypography unit converterConvert type and layout dimensions between DTP points, picas, CSS pixels, millimetres, centimetres and inches.
Units & convertersMass moment of inertia converterCompare mass moments of inertia in kg·m², kg·cm², g·cm² and pound-foot or pound-inch units.
Units & convertersSpecific volume converterConvert volume per mass between m³/kg, l/kg, cm³/g and ft³/lb without changing the material conditions.
Units & convertersMass flow rate converterConvert mass flow rates in kilograms, grams, tonnes or pounds per second, minute or hour.
Units & convertersMolar flow rate converterConvert molar flow rates between mol/s, mol/min, mol/h, kmol/h and mmol/s.
Units & convertersSurface tension converterCompare surface tension in N/m, mN/m, dyn/cm and pound-force per foot.
Units & convertersPorous medium permeability converterConvert intrinsic permeability of porous materials between m², µm², darcy and millidarcy.
Units & convertersLuminous intensity converterScale photometric luminous intensity between candela, millicandela and kilocandela.
Units & convertersLuminance converterConvert luminance between cd/m² or nit, stilb, lambert and foot-lambert.
Units & convertersIlluminance converterCompare illuminance in lux, kilolux, foot-candles and phot.
Units & convertersElectric charge converterConvert electric charge between coulombs, millicoulombs, microcoulombs and ampere hours.
Units & convertersLinear charge density converterConvert electric charge per length in C/m, µC/m, nC/m and units per centimetre.
Units & convertersSurface charge density converterConvert electric charge per area between C/m², µC/m² and units per square centimetre.
Units & convertersVolume charge density converterConvert electric charge per volume in coulombs or microcoulombs per cubic metre or cubic centimetre.
Units & convertersElectric current converterConvert electric current between amperes, milliamperes, microamperes, kiloamperes and abamperes.
Units & convertersLinear current density converterConvert current per length between A/m, A/cm, A/mm and mA/m.
Units & convertersCurrent density converterCompare electric current density in amperes per square metre, square centimetre or square millimetre.
Units & convertersElectric field strength converterConvert electric field strength between V/m, kV/m, V/cm, kV/cm and N/C.
Units & convertersVoltage converterScale voltage between volts, millivolts, microvolts, kilovolts and megavolts.
Units & convertersElectrical resistance converterConvert electrical resistance between ohms, milliohms, microohms, kiloohms and megaohms.
Units & convertersElectrical resistivity converterCompare material resistivities in Ω·m, Ω·cm, µΩ·cm and Ω·mm²/m.
Units & convertersElectrical conductance converterConvert electrical conductance between siemens, millisiemens, microsiemens, kilosiemens and the historical mho.
Units & convertersElectrical conductivity converterConvert conductivity of materials or solutions between S/m, S/cm, mS/cm, µS/cm and mS/m.
Units & convertersCapacitance converterConvert electrical capacitance between farads, millifarads, microfarads, nanofarads and picofarads.
Units & convertersInductance converterCompare inductance in henries, millihenries, microhenries and nanohenries.
Units & convertersMagnetomotive force converterConvert magnetomotive force between ampere-turns, kiloampere-turns and gilberts.
Units & convertersMagnetic field strength converterConvert magnetic field strength H between A/m, kA/m, A/cm and oersted.
Units & convertersMagnetic flux converterConvert magnetic flux between webers, milliwebers, microwebers and maxwells.
Units & convertersMagnetic flux density converterCompare magnetic flux density in tesla, millitesla, microtesla, nanotesla and gauss.
Units & convertersRadioactivity converterConvert radioactive activity between becquerels and curies, including their prefixes.
Units & convertersRadiation exposure converterConvert radiation exposure between coulombs per kilogram, millicoulombs per kilogram, roentgens and milliroentgens.
Units & convertersAbsorbed dose converterConvert absorbed dose between grays, milligrays, micrograys, rad and millirad.
Units & convertersEquivalent dose converterConvert equivalent dose between sieverts, millisieverts, microsieverts, rem and millirem.
Units & convertersLength converterConvert lengths from millimetres to kilometres, as well as inches, feet, yards, international miles and nautical miles.
Units & convertersArea converterCompare areas in mm², cm², m², hectares, km², square feet and acres based on the international foot.
Units & convertersVolume converterConvert volumes between millilitres, litres, cubic metres, cubic centimetres, US gallons and imperial gallons.
Units & convertersMass converterConvert mass between milligrams, grams, kilograms, tonnes, ounces and pounds.
Units & convertersSpeed converterCompare speeds in m/s, km/h, mph, knots and feet per second.
Units & convertersEnergy converterConvert energy between joules, kilojoules, megajoules, watt hours, kilowatt hours and electronvolts.
Units & convertersPower converterConvert power between watts, kilowatts, megawatts, metric horsepower (PS) and mechanical horsepower (hp).
Units & convertersPressure converterConvert pressure between pascals, hectopascals, kilopascals, megapascals, bar, psi and standard atmospheres.
Units & convertersTime duration converterConvert durations between milliseconds, seconds, minutes, hours, days and weeks.
Units & convertersTemperature converterConvert absolute temperatures between Celsius, Fahrenheit and kelvin. The limits of each scale are checked.
Units & convertersUnit converterConvert length, area, volume, mass, speed, energy, power, pressure and time in one tool.
Marketing & businessAI automation payback calculatorEstimate the working time saved by automation after human checks, error correction and maintenance. Compare the value of the freed capacity with the labour costs you expect to save in practice.
Marketing & businessPrice increase and sales volume calculatorSee how many sales are needed to maintain the previous total contribution with a new price and new variable cost. You can also compare your own sales assumption with the threshold.
Marketing & businessCard payment fee comparisonCompare two of your own offers based on the monthly fixed fee, turnover percentage, per-transaction fee and setup cost. You choose the number of months to examine.
Marketing & businessIn-house printing vs outsourcing calculatorCompare the in-house and external costs of a printing job of identical scope. We treat sheets and printed pages separately, even for double-sided documents.
Home & DIYDripping tap water loss and cost calculatorEstimate water loss from drops per minute, water collected over a measured time or a known hourly flow. See daily, 30-day and annual costs, plus an optional repair payback estimate.
Home & DIYLeaking toilet water loss and cost calculatorEnter an estimated hourly loss or compare two water-meter readings over a measured period. Subtract any known water use to estimate the unexplained flow and its water and wastewater costs.
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01Use your own valuesThe starting values are examples. Choose your own prices, time periods and units.
02Understand the resultFormulas and assumptions appear alongside your calculation.
03Use the resultCopy the result or download it as a CSV file.