How to calculate percentages: discounts, increases and VAT
The four most common percentage operations, with formulas and worked examples.
VAT and discount calculator
Add or remove VAT and apply discounts with an editable rate.
Runs in your browser
- Net amount
- 100.00
- VAT (21 %)
- 21.00
- Total incl. VAT
- 121.00
The rate is editable. Quick presets use Spain's rates (21 %, 10 %, 4 %); the UK standard rate is 20 %. This is not tax advice.
What it does: VAT and discount calculator
Work out a VAT-inclusive price from the net amount, recover the net amount from a final price, or apply a percentage discount. The result shows the full breakdown to two decimal places.
The rate is editable, so it works for any country's VAT or similar proportional sales tax.
How to use it
- Choose whether to add VAT, remove it or apply a discount.
- Enter the price and the rate (or tap a preset).
- Check the breakdown: net, VAT and gross — or original price, saving and final price.
Examples
Freelancer invoice
A net amount of 1,250 at 20 %: VAT of 250 and a total of 1,500.
Receipt breakdown
You paid 55 at a restaurant with 10 % VAT: net 50 and VAT 5.
Limits, formulas and assumptions
- Add VAT: gross = net × (1 + rate / 100).
- Remove VAT: net = gross / (1 + rate / 100). Simply subtracting 20 % from the gross is a common mistake that gives too low a net amount.
- Rounding to the cent may differ depending on how each invoice line is calculated.
- Results are for guidance only; ask a tax adviser about your specific case.
Frequently asked questions
Why can't I just subtract 20 % from the final price?
Because VAT is calculated on the net amount, not the total. From 120 the net is 100, not 96.
Which rate should I use?
It depends on the country and the product. Check your tax authority's current rates; the field accepts any value.
Does it work for other taxes?
Yes, for any proportional tax such as GST: just change the rate.
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