Comprehensive Guide
Learn more in our Business & Tax Guide.
How it works
vat / gst / sales tax calculator takes your inputs and produces net amount (excl. tax), tax amount, gross, rate applied. Add or extract VAT, GST or sales tax from any gross or net amount — the reverse calculation businesses do every invoice. You provide 2 inputs: Gross amount (incl. tax) (currency, in dollars) (default: 240 dollars); Tax rate (percent, in percent) (default: 20 percent). The calculator returns 4 outputs: Net amount (excl. tax) (the primary result); Tax amount (a secondary output); Gross (a supplementary figure); Rate applied (a supplementary figure). Business tax and finance calculations combine multiple moving parts — revenue, expenses, depreciation, tax brackets, and timing — in ways that make back-of-envelope estimates unreliable. This calculator handles the interaction of those variables precisely, so your business decisions rest on real arithmetic. The underlying formula: Net = Gross / (1 + rate/100) | Tax = Gross - Net With the default values, net amount (excl. tax) is computed from the interaction of every input field — change any one of them and the result updates immediately, so you can stress-test different scenarios without re-entering the whole form. Adjust the inputs to match your real financial situation. The defaults are realistic starting points, but every person's circumstances differ — your actual income, expenses, rates, and timelines will produce a different answer. Use the tool iteratively: start with the defaults, then change one variable at a time to see which factor has the largest impact on your outcome.Formula
Net = Gross / (1 + rate/100) | Tax = Gross - Net
Tips
- Never multiply gross by the rate to find tax — divide by 1 + rate instead.
- VAT returns reconcile net and tax separately; the extraction here is the line-item version.
- Different goods carry different rates in many jurisdictions (reduced, zero) — check the item's category.
- For small-business flat-rate schemes, the percentages differ — use your scheme's rate.
Frequently asked questions
How do I calculate VAT from a gross amount?
Divide the gross by 1 + (rate/100): at 20%, gross / 1.2 gives the net, and the difference is the VAT. Dividing by the rate itself instead understates the tax — the classic invoice error this calculator eliminates.
What is the difference between VAT and sales tax?
VAT is charged at each stage of production and offset along the chain, with businesses reclaiming input VAT; sales tax is charged once at retail. For the end customer the arithmetic is the same percentage on the price — the extraction works for both.
Do I charge VAT on every sale?
Only if you are registered (mandatory above revenue thresholds in most jurisdictions). Thresholds differ by country, and some goods and services are exempt or zero-rated. Verify your registration status and the category of each sale.
Why does the net price matter for VAT returns?
Returns report net supplies, output tax and input tax separately — the net is the base, not the gross. Extracting it correctly per invoice is the difference between an accurate filing and a penalty-finding audit.