Free calculators for UK trades
The sums every trades business should do once a year and most never get round to. No sign-up, no email wall, nothing to download. Every tax rate is taken from GOV.UK and carries the date we checked it, because a calculator running on a rate that changed two budgets ago is worse than no calculator at all.
Hourly rate calculator
What should I be charging an hour?
Works backwards from the take-home pay you want, your real overheads and the hours you can actually bill, which is never the hours you work.
Best for: Anyone who has never worked out their rate properly, or has not revisited it in two years.
Open the calculatorMarkup vs margin calculator
Is 20% markup the same as 20% margin?
No, and the gap costs real money. Converts between the two, shows your sell price, and includes a conversion table worth pinning up.
Best for: Anyone pricing materials, or quoting from a price book.
Open the calculatorVan running cost calculator
What does my van actually cost me per mile?
Totals fuel, insurance, tax, servicing, tyres and finance, then compares your real cost per mile against HMRC's mileage allowance.
Best for: Sole traders deciding whether to claim mileage or actual running costs.
Open the calculatorThe rates these tools run on
Published here rather than buried in the code, so you can check them yourself.
| Rate | Value | Applies to | Source |
|---|---|---|---|
| Mileage allowance, first 10,000 business miles | 55pRaised from 45p, the first increase since 2011. Backdated to 6 April 2026. | 2026 to 2027 tax year | GOV.UKChecked 2026-08-26 |
| Mileage allowance, each mile above 10,000 | 25pUnchanged. | 2026 to 2027 tax year | GOV.UKChecked 2026-08-26 |
| VAT registration threshold | £90,000Rolling 12-month taxable turnover. | Current | GOV.UKChecked 2026-08-26 |
Knowing the number is the easy bit
Getting the quote out the same day, and the invoice out before you get home, is what actually changes the year. That is the part Gafferly does.