About
About Margin Calculator
Margin Calculator is a browser-local Mycelgrid app for gross margin, markup, selling price, cost, and gross profit calculations.
Supported calculations
The app solves nine monetary input pairs across Cost, Selling price, Gross profit, Margin, and Markup, and separately converts Margin ↔ Markup without inventing a monetary scale. Optional quantity scales the monetary totals.
Calculation method
The engine parses ordinary decimal input into exact BigInt rational values instead of using binary floating-point accumulation as calculation truth. Repeating or very long display values can be rounded and are marked approximate.
Important boundaries
Margin uses Selling price as its denominator; Markup uses Cost. A zero denominator is explicitly undefined. Cost is the amount supplied by the user; the app does not automatically add taxes, shipping, fees, labor, overhead, advertising, returns, or other expenses and does not provide financial, tax, accounting, legal, or other professional advice.
Local-first behavior
Entered values and mode drafts live in page memory. The app does not create an account, cloud history, or recovery service. Share App shares the canonical app URL rather than entered values or results.
Privacy, data and limits
Margin Calculator processes entered pricing values, mode drafts, optional quantity, and current results only in this browser page. It does not upload calculator work or maintain an app-owned calculation history, account, cloud copy, or recovery service.
Results use deterministic decimal/rational arithmetic. Margin uses Selling price as its denominator and Markup uses Cost; a zero denominator is explicitly undefined rather than Infinity. Cost means the amount you enter and does not automatically include taxes, shipping, fees, labor, overhead, advertising, returns, or other expenses. The app provides general mathematical calculations, not financial, tax, accounting, legal, or other professional advice. Share App shares only the canonical app URL, not entered values or results.
For platform-wide practices, read the Mycelgrid Privacy Policy and Terms of Use. For a real product problem or accessibility issue, use Contact Mycelgrid.