Sales Tax and VAT Calculator Calculators
Add tax to a net price, or strip it back out of a gross price.
Sales Tax and VAT Calculator is a free online tool that add tax to a net price, or strip it back out of a gross price. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.
- Price
- Free — no account, no quota, no watermark
- Category
- Calculators
- Where it runs
- In your browser, on your device
- Files uploaded
- None
- Technology
- plain JavaScript
- Settings
- 4
- Works offline
- Yes, after the first visit
About Sales Tax and VAT Calculator
Removing tax is not the same as subtracting the rate. To strip a 20% tax you divide by 1.2, not multiply by 0.8 — the difference on $120 is $100 versus $96, and getting it backwards is one of the most common bookkeeping errors there is.
How to use it
- Enter amount, tax rate and the amount above is.
- Adjust the remaining 1 setting if the defaults do not fit your case.
The 4 settings
| Setting | What it does | Default |
|---|---|---|
| Amount | A numeric value. | 100 |
| Tax rate | A numeric value. | 20% |
| The amount above is | Choose from 2: Before tax (add tax), After tax (remove tax). | Before tax (add tax) |
| Currency | Choose from 7: USD $, GBP £, EUR €, INR ₹, AUD A$, CAD C$…. | USD $ |
Under the hood
| Runs on | plain JavaScript — runs the whole thing |
| Controls | Amount, Tax rate, The amount above is, Currency |
Questions
Why is the gross-to-net calculation different?
Because the tax was calculated on the smaller net figure. Going forwards you multiply by 1 + rate; going backwards you divide by the same thing. Subtracting the percentage overshoots every time.
What does the currency option change?
It offers 7 choices — USD $, GBP £, EUR € and INR ₹ and more. The default is USD $, which suits most cases; change it when your input or your destination calls for something specific.
Is the arithmetic exact?
It uses double-precision floating point — about 15 significant figures, far more than the inputs justify. Displayed rounding is cosmetic; the underlying numbers are not rounded between steps, so chained results do not drift.