Online Calculators & Tools

Counts the studs in a wall at 12, 16 or 24 inch centres, with plates, corners, partition backers and the kings, jacks and cripples around each opening.

Calories burned on a treadmill from belt speed, incline and time, using the ACSM metabolic equations rather than a flat MET value, so the gradient counts.

Adds up the ACR TI-RADS points for a thyroid nodule from its five ultrasound feature categories and reports the level with the published size thresholds.

Works out the tarot birth cards for a date using the Arrien and Greer method: month plus day plus year, reduced to 22 or less. Entertainment only.

Divides a polynomial by a linear factor using the synthetic division tableau, showing the bring-down, multiply and add row by row.

Converts a race time between short course yards, short course metres and long course metres using the published distance factor and per-turn adjustment.

Gives the tilt angle for a fixed solar array from your latitude, year-round and by season or by date, plus the row spacing that clears midwinter shade.

Payment on a fixed rate second mortgage running behind a first, with the two payments added together, the combined loan-to-value and the blended rate.

A starting figure for your weight belt from the published percentage-of-body-weight bands, adjusted for exposure suit and for fresh or salt water.

Reads 3, 4, 5 and 6 band resistor color codes into ohms with tolerance and temperature coefficient, and turns a resistance back into its bands.

Splits a sale commission between the listing and buyer sides, then through a referral, a brokerage split and a transaction fee to the agent's cheque.

Adds up what each part of a PC build draws, adds headroom, rounds to a size that is sold, and converts the load into draw at the wall.

Splits an amount in proportion to shares or units, or over part of a period, with the parts cut to whole cents that still add to the total.

Works out how many plants fit a bed at a given spacing, in straight rows or staggered, and how many it takes to cover an area of ground.

Works out the pavers, base stone, bedding sand and joint sand a patio needs from one set of measurements, with waste, edging and excavation depth.

Turns survey answers into a Net Promoter Score, from grouped totals or the full 0 to 10 spread, with the margin of error and a target tab.

Works out a mod n, adds, multiplies and raises to a power inside a modulus, and solves a x = b (mod n) to find modular inverses.

Converts Overworld coordinates to Nether coordinates and back at the fixed 1:8 ratio, and checks whether two portals will end up sharing a link.

Panel take-off for a metal roof: how many panels of a given coverage width, how long, how many seams, and what they cost at your price per linear foot.

Sodium or potassium hydroxide and water for a soap batch, from your oil weights, their saponification values and the superfat you choose.

Recalculates undergraduate grades the way LSAC summarizes them: an A+ worth 4.33, every repeated attempt counted, and penalty withdrawals counted as zeros.

Punnett square for a foal's colour across five tested loci: extension, agouti, cream, dun and grey, with the chance of each colour and the genotypes behind it.

Bands your height and wrist-to-floor measurement on the standard static fitting chart and lays the length adjustment over a full set of clubs.

Profit and loss on a futures position from the contract multiplier or the tick value, with commission, notional value, leverage and return on margin.

Puts numbers in place of the letters in an algebraic expression and works out the result, showing the substitution and one operation per step.

Reduces a fraction to lowest terms and lists fractions equal to it, checks whether two fractions match, and fills the gap in a statement like 3/4 = ?/20.

Works out a dwelling's calculated load in volt-amperes by the NEC Article 220 standard method or the 220.82 optional method, from nameplate ratings you enter.

Checks whether one whole number divides another, shows the remainder and names the divisibility rule, or tests a number against every divisor from 2 to 100.

Builds a matrix of destiny chart from a birth date: the four square points, the four diagonals, the centre and the purpose ladder, with the working shown.

Solves ax^3 + bx^2 + cx + d = 0 by Cardano's method and returns all three roots, including complex ones, with the discriminant.

Add, subtract, multiply and divide complex numbers, convert between a + bi and polar form, and take integer powers and all nth roots by De Moivre.

Rewrites a quadratic as a squared bracket plus a constant and shows every step, then solves it by taking a square root instead of quoting the formula.

Builds a vinyl wrap estimate from film, waste, fitting hours and extras at your own prices, or breaks a quote you already have into film and labour.

Scores a ten-pin game frame by frame from the rolls you write down, showing how each strike and spare carries into the frames after it.

Splits your weight into fat and lean mass and moves them in opposite directions, so a recomposition shows up where the scale hides it.

Compares an accelerated biweekly schedule with monthly payments on the same loan: the payoff date, the time cut off the term and the interest saved.

All four BaZi pillars from birth details: year, month, day and hour, with the year turning at Lichun and the months set by the sun's ecliptic longitude.

Works out an aircraft loan payment, including the balloon these notes often carry, then adds hangar, insurance and fuel to give a cost per flight hour.

What a print costs to run: filament or resin, electricity, printer depreciation, your time and a failure allowance, plus a price at the markup you set.

The smallest copper conductor that carries the load and holds voltage drop, from NEC Table 310.16 with ambient, conduit fill and continuous load applied.

Rolls of wallpaper for a room, worked out from the wall run, the ceiling height, the pattern repeat and the width and length of the roll.

Work out your VDOT from one race result, see the equivalent times at nine other distances, and turn it into the Daniels E, M, T, I and R training paces.

Works the t statistic out from sample means, standard deviations and sizes, one sample or two, and gives the degrees of freedom, the p-value and the critical t.

Recommended surfboard volume in litres from your body weight, ability and the waves you surf, using the published Guild Factor shortboard bands.

Counts the time since a date you enter: days, weeks, whole months, a years-months-days breakdown, and the dates the usual day and year marks fall on.

Works out siding in squares and boxes from wall area less doors and windows, with a waste allowance, and totals the cost at your own prices.

Calculates serum osmolality from sodium, glucose and urea in US or SI units, and returns the osmolal gap when you add a measured osmometer result.

Return on a rental across the whole time you hold it, with the profit split into cash flow, appreciation, principal paid down and the costs of the deal.