One Swiss Knife in the exact shape of your life.

Percent & VAT

A percent-and-VAT reckoner that runs in your browser: gross to net, net to gross, no account required.

Live · runs in your browser · no network

This is not a screenshot. It's the real tool, running right here: go on, put something in it.

Open the demo full-screen: /demos/percent-vat.html

Forged into a knife, this tool ages with use: the blades you reach for wear soft, entries you tend keep their bloom, and the years travel with the file through every reforge.

The invoice says plus VAT, the sale says forty percent off, and your brain says please, not before coffee. Percent & VAT handles the small arithmetic of money — percentages up and down, tax added on or peeled back out of a gross price. It gives you the number and forgets the question, which is exactly what you want from a calculator.

KindReckoner · computes, stores nothing
CategoryReckoners
Weight1
Manual:

Standing facts

In ten years

Percent & VAT computes; it doesn't hoard. Open the file in 2036 and it will do the same arithmetic it does today, because the arithmetic is written into the file and nothing about it needs a server to agree.

If Offline.Ltd closes tomorrow, nothing on your machine notices. That isn't a marketing promise; it's simply what a file is.

Getting your data out

There is nothing locked in to get out: copy the numbers, or keep the file. Either way you owe no one a request form. No export queue, no "we'll e-mail you a link within 48 hours", no format that only one vendor can read.

Copy the file to a USB stick, a NAS, a folder your devices already sync. It runs on Windows, macOS, Linux, Android and iOS, online or off, because a browser is the only thing it ever needed.

Who else sees this

Nobody. Percent & VAT works out its answer in your browser and forgets it the moment you close the tab: there is no store to breach, because nothing is stored. There is no account, no telemetry, no analytics, and no code in the file that opens a network connection, pull the cable and watch it carry on working. How privacy works across the Reckoners tools →

Questions people ask

01

How do I work out the price before VAT from a total?

Give it the gross amount and the rate, and it peels the tax back out to show you the net. It works in the other direction too, for when you are the one writing the invoice.

02

Is it safe to type real invoice amounts into this?

Yes — it computes in your browser, offline, inside a single HTML file, and stores nothing. Your figures never leave the page and there is no account, no server, no one else's spreadsheet.

03

Who is Percent & VAT for?

Freelancers pricing work, shoppers checking a discount actually is one, and anyone who regularly needs a percentage and does not trust themselves to move the decimal point under pressure.

Go deeper on Percent & VAT

More Reckoners

Fits your knife at weight 1. Nothing here is final, Knife follows Life. Reforging within your tier is free, forever. Add it, drop it, reforge it later; the file stays yours either way.

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