Online Calculators & Tools

Builds an itemised cost for a garage from its size and your own rates: slab, framing, siding, roof, doors and wiring, attached or detached.

Costs a recipe per serving from ingredient quantities and pack prices, gives the food cost percentage against a menu price, and the price a target food cost needs.

Adds up a fantasy football stat line under your own league settings, with PPR, half PPR and standard presets and every point value as an editable field.

Evaluates a^(bx+c)+d at a point, solves it for x, turns a growth rate into a doubling time and half life, and fits a curve through two readings.

Works out the drop from a level line over any distance, how far away your horizon is, and how much of a distant object the curve hides from view.

Splits a fill between the E85 pump and the gasoline pump to hit a target ethanol content, and works out what a partial fill actually left in the tank.

Works out the vertical jump you need to touch the rim, hang on it or dunk with the ball clearing, and runs it backwards from a vertical you already have.

Works out joint compound by the pound and by the bucket for a board area, split across the tape, fill and finish coats, with the tape and screws to match.

Turns bust, waist and hip into a US, UK and EU dress size across the misses and plus ranges, and says which to take when the three disagree.

Builds f(g(x)) and g(f(x)) from two standard forms with your own coefficients, shows the substitution and evaluates both at any x you pick.

Adds up a day's caffeine from coffee, tea, cola and energy drinks against the 400 mg figure, and decays a dose over the hours to work out what is left.

Works out the BUN to creatinine ratio from conventional or SI laboratory units and places it in the low, normal, raised or markedly raised band.

Saddle height from your inseam by the LeMond and Hamley formulas, each named and kept separate, plus what a crank or shoe change does to it.

Works out how many balusters fill a railing opening, the even gap they leave and where to mark the rail, keeping every gap under the 4 inch sphere rule.

Finds the monthly payment on a loan amortised over a long schedule but due years earlier, and the lump balloon balance left owing on that date.

Works out the monthly payment on a balloon mortgage, the lump that falls due at five or seven years, and what refinancing that balance at a new rate would cost.

Works out how long an audiobook takes at a chosen playback speed, how much time that saves, and the speed you need to finish it by a deadline.

Finds the inverse sine of a value in degrees, radians and gradians, states the principal value range, and refuses anything outside -1 to 1 with a reason.

Converts an A1C percentage to estimated average glucose and back again, using the ADAG relation, with every result given in both mg/dL and mmol/L.

Projects a 403(b) balance at retirement from your salary, deferral rate, employer match and expected return, and applies the age 50 and 15-year service catch-ups.

Finds your western star sign from a birth date, with its element, quality, ruling planet and opposite sign, and says when a date sits on a boundary.

Converts VA to watts at a power factor and back again, with the reactive power in var, the phase angle and the current for a single or three phase supply.

Estimates how long a UPS or inverter battery bank holds a load, from the bank capacity in amp hours, the system voltage, inverter efficiency, depth of discharge and Peukert exponent.

Works out how a tire's gauge pressure changes with temperature or altitude, using the gas law and the standard atmosphere, in psi, bar and kPa.

Estimates a tattoo price from the shop hourly rate and minimum charge, the size of the design, and detail and placement factors you can change yourself.

Swimming pace per 100 and per 50 in both yards and metres, from a swim you have done or a target pace you mean to hold, with cumulative splits.

Turns a measured foot length in centimetres or inches into US men's, US women's, UK, EU and Mondopoint shoe sizes on a named conversion basis.

Turns a set's weight, reps and RPE into a percentage of your one rep max, and works the other way to give the weight for a target RPE.

Counts a whole roofing load: squares, shingle bundles, underlayment rolls, ice and water shield, starter strip, hip and ridge cap, drip edge, valley metal and nails.

Counts the trusses a building needs from its length and spacing, and works out the run, rise, slope and chord lengths of a common truss.

Counts the rebar in a slab grid: bars each way from the spacing and edge cover, total linear feet, weight, and how many stock bars to buy with lap splices.

Scores the Revised Cardiac Risk Index from its six criteria and returns the point count and the risk class, without attaching a percentage the sources disagree on.

Estimates quarter mile ET and trap speed from race weight and horsepower using the Hale, Fox and Huntington formulas, and works backwards from a timeslip.

Prostate volume in cc from the three dimensions on an ultrasound or MRI report, using the ellipsoid formula, plus PSA density when a PSA value is entered.

Works out how much potting mix a round pot, rectangular planter or window box takes, in litres, cubic feet, dry quarts and whole bags.

Turns a waist and inseam measurement into a pants size: the US number, the letter, the EU and UK numbers and the W by L tag denim is sold by.

Works out the osmolarity of a solution in mOsm/L from the molar concentration of each solute and the number of particles it dissociates into.

Multiplies decimals and shows the working: the whole-number multiplication in a column, how many decimal places the factors carry, and where the point goes.

Turns a coverage area and depth into cubic yards, tons and bag counts for decorative landscape rock, using the density of the rock you actually chose.

Works out your K/D and KDA from kills, deaths and assists, and how many more matches it takes to drag a lifetime ratio up to a target.

Turns a fasting protocol and one meal time into clock times: when the eating window opens and closes, when the fast ends, and the halfway point.

Works out a heating and cooling load from the building envelope itself: wall and ceiling areas, R-values, window U-values, air changes, solar gain and internal gains.

Adds, subtracts, multiplies and divides hexadecimal numbers, and runs AND, OR, XOR, NOT and the shifts, with every answer given in hex, decimal and binary.

Daily calorie needs from the revised 1984 Harris-Benedict equations, with the original 1919 figures and Mifflin-St Jeor shown beside them.

Works out how much hardwood a floor takes: the square footage, the waste allowance, the number of boxes to buy and the board and row count.

Prices a hardwood floor installed: boards plus waste, labour, sanding and finishing, fasteners, underlayment, removing the old floor and the trim.

Finds the date six calendar months after a birthday, the weekday it falls on, how far away it is, and the age reached on that day.

Turns your own weekly spend per adult into a monthly and yearly grocery budget for the household, counting teenagers and children separately.