---
title: "About | Citrus Carton"
description: "Citrus Carton is a set of free calculators for discounts, multi-buys, sale prices, sales tax, VAT and tips. Everything is worked out in your browser."
url: https://citruscarton.shop/about/
---

# About Citrus Carton

Checkout maths, done properly: what a discount really saves, what a deal really costs, and what's tax.

## What it is

Citrus Carton is six small calculators for the sums that come up when you shop: percent off, discounts stacked on top of each other, buy-one-get-one-free and other multi-buys, the original price behind a sale price, sales tax and VAT, and tips split between friends. Each page shows its formula and a worked example, so you can check the answer yourself.

## How it works

Everything runs in your browser. The formulas are part of the page, so nothing you type is sent anywhere, and once a page has loaded it keeps working without a connection. There are no accounts, cookies or ads.

## What it is not

It is not a price checker or a tax adviser. It doesn't know what any shop charges or which tax rate applies to your purchase: it works with the numbers you enter. The tax rates on the sales tax page are published standard rates given as examples, with links to the tax authorities; rates change, so check the current one before you rely on it.