These 4 example calculation forms were initially created in Microsoft Excel and then converted to JavaScript.

The first example is a mobile form that uses PHP Data Objects (PDO) to look up values in a SQL database.
Enter characteristics and carat weight to run a query that returns a price per carat value to calculate stone price.

The second example is a larger calculation worksheet that uses Excel formulas and functions to calculate values.
Click here to open the worksheet in a new tab. Please use Chrome or Edge web browser for the best experience.

The third example is a web-enabled spreadsheet that calculates a loan repayment schedule up to 40 years.
Enter the loan amount, interest rate, loan period, and a start date to generate the schedule.

The fourth example is a web-enabled invoice that uses Excel's VLOOKUP function to populate form values.
Enter a Customer ID and then add line items using the dropdown menus. Enter quantities to calculate results.