Tools
Free UK calculators for self-employed people, company directors and households. Each one shows its workings and links the GOV.UK rates it uses.
All calculators
VAT calculator (UK)
Add VAT to a price or remove it from a total at 20%, 5% or any rate, with the working shown.
20%standard rateDo I need to charge VAT? (UK)
Check whether you need to charge VAT and at what rate (20%, 5%, 0% or exempt), based on registration, what you sell and where your customer is.
20 / 5 / 0%VAT ratesSelf Assessment late penalty calculator (UK)
Work out late filing penalties, late payment penalties and interest on a 2025/26 tax return due 31 January 2027.
31 Jan2027 deadlineFinancial check-up (UK)
Quick prompts for common money opportunities: ISA headroom, child benefit charge risk, pension reminders and more. Estimates only.
£20,000ISA allowanceMileage vs actual vehicle costs (UK)
Compare HMRC simplified mileage vs actual running costs using your business miles and (optional) annual costs.
55pper mile 2026/27Sole trader vs limited company (UK)
Rough take-home comparison using simple profit + salary/dividend assumptions. Estimates only.
19–25%corporation taxVAT threshold calculator (UK)
Check your rolling 12-month turnover against the £90,000 VAT threshold and get your registration deadline.
£90,000rolling 12 monthsUK VAT number checker
Check a UK VAT number’s format and check digits, then confirm it with HMRC’s official lookup.
GB + 9digits