App recipes
How to build a calculator web app with Div-idy
Div-idy can build browser-based calculators for quotes, quantities, measurements, scores, and other rule-based results. Supply the formula, inputs, units, and rounding rules. The generated React app can recalculate as values change or after a Calculate action, explain the result, and optionally collect a separate inquiry through the project database.
Start with the calculation, not the screen
List each input, its allowed range, default value, and unit. Explain the formula in plain language or mathematical notation. Include how to handle blank values, zero, decimals, and values outside the permitted range.
Decide when rounding happens and whether the displayed result is an estimate. If a real quote depends on an inspection or staff approval, say so in the app. Generated calculations should follow your supplied rules rather than invent business terms.
Example: a materials calculator prompt
Build a mobile-friendly mulch calculator. Accept rectangular bed length and width in feet, depth in inches, and bag size in cubic feet. Calculate volume as length × width × depth ÷ 12, then divide by bag size and round the bag count up. Show the unrounded volume to two decimals, the formula, and a Reset button. Reject negative values and a zero bag size.
A 10-foot by 6-foot bed at 3 inches deep requires 15 cubic feet. With 2-cubic-foot bags, the purchase quantity is 8 bags. Give Div-idy examples like this to make the intended result unambiguous.
Make the result easy to understand
Ask for labels with units, readable output, and validation beside the relevant input. Keep assumptions visible near the result. For instant updates, define what appears while required values are incomplete; do not display a misleading zero or invalid number.
Use touch-friendly controls and a layout that keeps inputs and output easy to compare. A breakdown can be more useful than a single total when users need to understand the calculation.
Does a calculator need AI or a database?
A deterministic calculator can run entirely in the browser without an AI request or database. Device-local storage can remember preferences if requested. A separate “Request a quote” form can submit selected inputs and a concise result to the owner.
Keep that submission distinct from the calculation. Display confirmation only when the request succeeds, and preserve the entered values if it fails.
Verify the formula with known cases
Test a normal case, a rounding boundary, a decimal, zero where allowed, and invalid input. Change each field and confirm that the result updates correctly. Check units and reset behavior on a phone. For specialized calculations, have the formula reviewed before publishing; a successful build does not establish domain accuracy.