This JavaScript will validate an ABA routing number according to a given algorithm. (Although the number may be valid, it may not be actually assigned to a financial institution.)

It's a calculator that floats on the page. Drag it around and use it the same way you would the normal Windows calculator. Nice looking too.

An interesting script for converting between integers and Roman Numerals, as well as checking the validity of Roman Numerals for common mistakes.

Provides all the basic functions, including finding the square root. A small but powerful script.

JavaScript can sort data based on any field of information. In this example, a checkbook register can be sorted by date, check number, check amount, or paid to person. We're one step closer to online banking.

Modifies a number by adding commas after every third digit. For example, 123456789 is converted to 123,456,789. The script example shows this JavaScript as used on numbers of various sizes. And, it demonstrates a clever use of the modulus operator.

Calculates resistance from colors and colors from resistance, each with image-based output. Both color and numeric interfaces function as input and output.

Trying to keep track of gasoline expenses? This JavaScript calculates how many miles you are getting per gallon - per day and per year. It also calculates the amount spent per year and how much CO2 your car is producing.

Calculate whether or not a number is prime and break it into its prime factors. Also includes a loading bar for large numbers.

Convert units from one to another. Simply choose the unit you want to use, type the value in the field next to it, and click the 'Convert' button.