These Javascript devices calculate the scaled length (the output) when you enter the length of an object (the input) and a scaling factor (the scale). Metric conversions are supported.

These calculators are pretty simple; all they do is multiply and divide. The "Scale Down" calculator is useful for modeling from 1:1 objects since you can put in the actual 1:1 size measurement of an object in inches (as they're frequently provided), and it will output the scaled size in metric, which is easier to work with. You'll still have to do any preliminary feet-to-inches conversions yourself unless you enter the numbers in the spreadsheet-like syntax, shown below.

*ENTERING FRACTIONS: Expressions entered in the boxes are evaluated before being further processed. Interestingly, if you input a mixed measure like "12-1/2" instead of "12.5", it evaluates the expression as "12 minus 1 divided by 2", the result of which is "11.5". Therefore, you can enter fractional inches if you input the value as "12+1/2" (using "plus" instead of "minus"). The expression will be evaluated as a decimal value. However, if you input the measure as "12 1/2" (without the "plus" or "minus" operator) you will cause a Javascript error because that doesn't evaluate to anything (The "space" character is not a valid mathematical operator).

Because it evaluates the expression you enter, you can enter something like (5*12)+4+(3/4), which is like saying "five feet four and three-quarter inches" (5 feet times 12 inches plus 4 inches plus 3/4 of an inch).