Free tools

Calculators for everyday business decisions

GST, prices, credit and stock, worked out in your browser with the method and sources shown. No sign-up. Each result carries on into MatruOS, and nothing you type leaves the page unless you ask us to email it.

Free, no sign-up13 tools

Software cost calculatorOpen
AI team savings calculatorOpen
GST calculatorOpen
Margin and markup calculatorOpen
Price for a target marginOpen

The sums run in your browser.

What this solves

Common business decisions are made without the arithmetic

01Today

Whether a price covers cost after GST, how much working capital a credit policy ties up, or what a late-paying customer costs. The sums are simple, but they are rarely done before the decision.

02In MatruOS

These free calculators do the arithmetic with India's GST and business rules, explain each assumption and show the source, and carry the result into MatruOS if you want to act on it.

03What changes

A clearer number before the decision, with no sign-up needed to use the tool.

Free toolSoftware cost calculatorWhat your separate apps, set-up fees and copying time cost, against one MatruOS plan.Free toolAI team savings calculatorThe hours a month MatruOS's AI team could take, task by task, after plan and top-up costs.Free toolGST calculatorAdd GST to a price or take it out, with the CGST, SGST, UTGST or IGST split.Free toolMargin and markup calculatorProfit, markup and margin for one item or a whole price list.Free toolPrice for a target marginThe selling price that keeps the margin you want, with GST and price rounding.Free toolGSTIN format checkerCheck a GSTIN's state, PAN, holder type and check digit before you bill.Free toolInvoice series checkerPaste your invoice numbers to find gaps, repeats and numbers that break Rule 46.Free toolCost of credit calculatorWhat the credit you give customers costs you each month, and what paying sooner saves.Free toolBreak-even calculatorUnits and sales you need each month and each working day to cover your costs.Free toolGST late fee and interest calculatorLate fee and interest for GSTR-3B, GSTR-1, GSTR-4 and GSTR-9, from the due and filing dates.Free toolReorder level calculatorWhen to reorder one item or a whole list, and which items need ordering today.Free toolDays of stock calculatorHow many days of sales your stock covers, your stock turns, and the cost of extra stock.Free toolCash discount calculatorWhether to take or offer an early-payment discount, at your own borrowing rate.

Run the whole business on one system Set up for your trade.

Describe your business once. MatruOS sets up your apps, brings in your data and puts Muni and the AI team to work, with your approval on every step that matters. 7-day free trial, no card needed.

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