Calculate anything.
Answers you can check: every calculator shows its formula, its assumptions and where the numbers come from.
Home & construction
- Concrete CalculatorSlab volume, bags to buy, waste allowance.
- Square Footage CalculatorEnter the length and width to get the area in square feet, square yards and square metres.
- Tile CalculatorEnter the area and your tile size to see the tiles needed, the boxes to buy and the spares left over.
- Flooring CalculatorEnter the room area and the coverage printed on the box to see how many boxes to buy.
- Roofing CalculatorEnter the footprint and the pitch to get the true sloped area, in square feet and in squares.
- Fence CalculatorEnter the run and your spacing to see the posts, sections, rails and pickets.
- Mulch CalculatorEnter the bed area and the depth you want to see the volume and the bags to buy.
Math
- Percentage CalculatorEnter a percentage and a number to see the amount, plus the totals with it added and removed.
- Percentage Change CalculatorEnter the starting value and the new value to see how much it changed, in percent.
- Percentage Difference CalculatorEnter two values to compare them without either one being treated as the starting point.
- Fraction to Decimal CalculatorEnter a numerator and a denominator to see the decimal, the percentage and the simplest form.
- Ratio CalculatorEnter two quantities to see the ratio reduced, split as percentages and expressed as 1 to n.
- Probability CalculatorEnter the probability of each event to see how they combine.
- Bayes Theorem CalculatorEnter how common the condition is and how the test performs to see what a positive result really implies.
- Combination CalculatorEnter how many items there are and how many you take to see the combinations and permutations.
- Z-Score CalculatorEnter a value with the mean and standard deviation of its distribution.
- Confidence Interval CalculatorEnter your sample mean, standard deviation and size to see the interval around it.
- Sample Size CalculatorEnter the margin of error you want and the size of the group you are studying.
- Average CalculatorPaste or type your numbers, separated by spaces, commas or line breaks.