VAT Calculator
Use this VAT calculator to add VAT to a net price or remove VAT from a VAT-inclusive total. It supports common UK rates but does not decide whether a supply is taxable, exempt or zero-rated.
Quick answer
Choose add or remove, enter the amount and rate, and the calculator separates the net value, VAT amount and gross value.
Calculator
How to use this calculator
- Enter the figures that match your current scenario.
- Check the effective date, assumptions and any jurisdiction or plan selection.
- Review the breakdown, test a second scenario and verify the result before acting.
Explanation
What it is
Choose add or remove, enter the amount and rate, and the calculator separates the net value, VAT amount and gross value.
How it works
When adding VAT, the rate is applied to the net amount. When removing VAT, the gross amount is divided by one plus the VAT rate before the VAT portion is calculated.
When to use it
Use this tool to explore a planning scenario before checking current official rules, product documents or professional guidance.
Limitations
- The result is an estimate based only on the inputs shown.
- Rates, thresholds and product terms can change after the effective date.
- The calculator does not replace an official assessment, provider quote or personalised advice.
Key terms
- Estimate
- A planning result produced from the stated inputs and assumptions, not a guaranteed outcome.
- Effective date
- The date or tax year for which a changing rule, threshold or rate has been checked.
- Authoritative source
- An official or regulator-backed source used to support a rule, rate or calculation method.
Formula
How we calculate this
When adding VAT, the rate is applied to the net amount. When removing VAT, the gross amount is divided by one plus the VAT rate before the VAT portion is calculated.
Statutory or methodological reference:GOV.UK official guidance — How Vat Works.
Formula trace: Net/gross VAT arithmetic with selectable rate and rounding method; separate Flat Rate Scheme logic and invoice-level edge cases.
Worked example
For a VAT-inclusive price of £120 at 20%, the net amount is £100 and VAT is £20. This does not establish the VAT liability of the supply. Check the governing rule at GOV.UK official guidance — How Vat Works.
FAQ
What does the vat calculator calculate?
Choose add or remove, enter the amount and rate, and the calculator separates the net value, VAT amount and gross value.
Which assumptions have the biggest effect?
The most important assumptions are the amounts, time period, applicable rate or threshold, and any jurisdiction or plan choice shown in the form.
How accurate is this estimate?
It is designed for planning and testing scenarios. Accuracy depends on the inputs and whether your circumstances fit the simplified method described on the page.
Can I use the result as a final decision?
No. Verify changing rules and product terms, and seek suitable professional or official guidance when the decision is material or complex.
When should I recalculate?
Recalculate after a change in income, balance, rate, term, household circumstances, tax year or official policy.
Common mistakes
- Using a headline rate without checking whether it applies to the full amount.
- Mixing monthly and annual figures.
- Treating an educational estimate as an official assessment or guaranteed quote.
Tips
- Test a cautious scenario as well as an optimistic one.
- Keep a note of the assumptions and effective date.
- Compare the result with official guidance or provider documents before acting.
Related calculators
Related guides
Sources and editorial review
- GOV.UK official guidance — How Vat Works
- GOV.UK official guidance — Register For Vat
- GOV.UK official guidance — Vat Rates
Author and review
Author: FinanceHub UK Editorial Team — Editorial. Editorial policy.
Reviewed by role: VAT specialist / chartered tax adviser. Named qualified reviewer sign-off is pending before production.
Review record date: 2026-07-10. Next review due: 2027-03-01.