POS System with Customer Ledger – Google Sheets Apps Script

A shop counter that runs on a Google Sheet. Ring up a sale, the invoice prints, the stock drops, the customer's ledger updates and the day's chart moves — all in the same action, with a React front end and no database bill behind it.

At the counter

Products carry images so staff pick by sight rather than by code. Add to the sale, take the payment, generate the invoice. Stock is adjusted in real time as items leave, and anything falling below its threshold raises a low-stock notification before the shelf is empty. Returns and refunds are processed properly — the stock goes back and the sale is corrected, instead of being fixed by hand later.

Customers and what they owe

Each customer has a record and a ledger, so partial payments and running balances are visible per person rather than guessed from a pile of invoices. Payment tracking sits alongside it, which is what makes this usable in shops where regulars pay at the end of the month.

Knowing how the shop is doing

Sales analytics and charts cover what sold and when, and salesperson performance is tracked per user — useful the moment more than one person is on the till and commission or targets come into it. Logins are per user, with registration built in.

What it runs on

React 18 served from Apps Script, Google Sheets as the database. No hosting, no server, no monthly software fee, and the raw data stays in a sheet you can open and export. The currency symbol is configurable, so the same build works in any market.