Interest at 8% above Bank Rate plus £40, £70 or £100 compensation on overdue business invoices.
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Free business calculators
Quick, sourced calculators for the money questions small businesses ask most: late payments, VAT, what to charge and when invoices are due.
Add or remove VAT at 20%, 5% or 0%, or any custom rate for another country.
Turn your pay, costs, billable hours and margin into an hourly rate, day rate and job price.
Due dates for net 7, 14, 30 and 60 terms, in calendar or business days, skipping UK bank holidays.
For guidance only, not legal or tax advice.
Each calculator shows its working, cites the official sources it uses and runs in your browser. Then see which tools can do the job for you every time.
Questions people ask
Are these calculators free?
Yes. There is no sign up, and what you type stays in your browser.
Where do the figures come from?
The Bank of England for Bank Rate, legislation.gov.uk for the late payment rules, and GOV.UK and HMRC for VAT, bank holidays and payment terms. Each page lists its official sources.
Can I rely on the results?
Use them as a guide. They are for guidance only, not legal or tax advice. For a disputed debt or a tricky VAT question, speak to an accountant or a solicitor.
Your figures stay in your browser; nothing you type is sent to us.
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